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Dr Mikhail Lapine

Biography

PhD (summa cum laude): 2004, Osnabrück University.

Post-doctoral research experience:

2005-2007: Radio Laboratory, Helsinki University of Technology, Finland
2008-2010: Dept. Electronics and Electromagnetics, University of Sevilla, Spain
2010-2011: Nonlinear Physics Centre, Australian National University, Canberra, Australia
2011-2012: Metamaterials Lab, ITMO University, St.Petersburg, Russia
2012-2014: CUDOS, School of Physics, University of Sydney, Australia.

Joined the University of Technology Sydney in November 2014

Professional

Editor, "Metamaterials" (Elsevier), 2007–2012; "Photonics and Nanostructures" (Elsevier) since 2012; Associate Editor with Scientific Reports (NPG) since 2013.

Project Leader for Functional Metamaterials and Metadevices project with ARC Centre of Excellence for Ultrahigh bandwidth Devices for Optical Systems (CUDOS).

Member of European Physical Society and Australian Optical Society.

Reviewer for Nature Materials, Nature Physics and Nature Communications; Physical Review Letters and Physical Review A, B, E; Advanced Materials and Advanced Optical Materials; Applied Physics Letters and Journal of Applied Physics; Optics Express, JOSA B and other OSA journals, several IoP, IET and IEEE journals, and other scientific periodicals.

Image of Mikhail Lapine
Associate Professor, School of Mathematical and Physical Sciences
PHYSICS, ENGLISH, PHYSICS
 
Phone
+61 2 9514 1723

Research Interests

Theoretical electrodynamics with a specific interest to effective medium description of metamaterials as well as development of nonlinear, tunable and reconfigurable metamaterials, and introducing novel degrees of freedom to metamaterial design.

Chapters

Powell, D.A., Liu, M. & Lapine, M. 2015, 'Coupled electromagnetic and elastic dynamics in metamaterials' in Shadrivov, I.V., Lapine, M. & Kivshar, Y.S. (eds), Nonlinear, Tunable and Active Metamaterials, Springer Verlag, Germany, pp. 59-87.
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Metamaterials are well established in the field of electromagnetism, where they have demonstrated a wide variety of exotic material properties. More recently, mechanical metamaterials have also been shown to be quite promising in achieving exotic properties for acoustic waves. Here we discuss an emerging class of metamaterials with both electromagnetic and elastic properties, which are coupled to each other, giving rise to a new range of metamaterial properties. In particular, this can yield a very strong nonlinear response, including bistable states and self-oscillations. We present several structures which exhibit these properties, and experimentally demonstrate their feasibility.

Conferences

Smith, M.J.A., de Sterke, C.M., Kuhlmey, B.T., Poulton, C., Lapine, M. & Wolff, C. 2016, 'Suppression of Stimulated Brillouin Scattering in composite media', 2016 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD), 16th International Conference on Numerical Simulation of Optoelectronic Devices, IEEE, Sydney, pp. 23-24.
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Overcoming stimulated Brillouin scattering (SBS) is a major challenge in optical telecommunications networks and in fiber lasers. We evaluate the SBS gain coefficient for an all-dielectric composite material comprising a cubic, subwavelength array of spheres in a uniform background. We demonstrate total SBS suppression in fused silica using GaAs spheres
Smith, M.J., de Sterke, C.M., Kuhlmey, B., Wolff, C., Lapine, M. & Poulton, C. 2016, 'Elastic modelling of electrostriction in dielectric composite materials', Photonics and Fiber Technology 2016 (ACOFT, BGPP, NP), Photonics and Fiber Technology 2016 (ACOFT, BGPP, NP), OSA, Sydney, Australia.
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The electrostriction of a composite material does not only depend on the electrostrictive properties of the constituents, but also includes an additional mechanical response term. We compare two different models to calculate this contribution
Lapine, M., Poulton, C.G. & McPhedran, R.C. 2016, 'On the deviation of metamaterial spheres from effective medium', 2016 10th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2016, International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), IEEE, Chania, Greece, pp. 196-198.
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© 2016 IEEE.We analyse the convergence of the actual properties of finite subwavelength metamaterial samples where all the prerequisites for a reliable effective medium description, except for the finite size, are fulfilled, towards the effective medium predictions. We show that the convergence is rather slow and it is likely that hundreds of thousands of individual meta-atoms must be assembled together before the properties of the resulting structure can be claimed to correspond to those a bulk material. These observations are directly relevant for practical design of metamaterials and their future development.
Lapine, M. 2016, 'Strong boundary effects in microwave metamaterial samples', Proceedings of the 2016 IEEE Radio and Antenna Days of the Indian Ocean, RADIO 2016, IEEE Radio and Antenna Days of the Indian Ocean (RADIO), IEEE, St. Gilles-les-Bains, Reunion, pp. 1-2.
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© 2016 IEEE.The majority of metamaterial ideas are expressed in terms of effective material parameters. However, in many cases that kind of description fails, for a number of reasons such as strong spatial dispersion. One of the less known problems stems from the finite size of realistic metamaterials, which makes the total number of individual elements insufficient for an effective medium description, and promotes significant boundary effects. We present an analysis of this situation and point out that even for ideally shaped metamaterial samples there is a remarkable difference from theoretical predictions. As an example, we report the implications of finite size for metamaterial lenses.
Smith, M.J.A., Kuhlmey, B.T., de Sterke, C.M., Wolff, C., Lapine, M. & Poulton, C.G. 2016, 'Elastic modelling of electrostriction in dielectric composite materials', Optics InfoBase Conference Papers.
© 2016 OSA.The electrostriction of a composite material does not only depend on the electrostrictive properties of the constituents, but also includes an additional mechanical response term. We compare two different models to calculate this contribution.
Smith, M.J.A., Kuhlmey, B.T., Martijn de Sterke, C., Wolff, C., Lapine, M. & Poulton, C.G. 2016, 'Elastic modelling of electrostriction in dielectric composite materials', Optics InfoBase Conference Papers.
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© OSA 2016.The electrostriction of a composite material does not only depend on the electrostrictive properties of the constituents, but also includes an additional mechanical response term. We compare two different models to calculate this contribution.
de Sterke, C.M., Duncan, C., Perret, L., Palomba, S., Lapine, M. & Kuhlmey, B.T. 2015, 'Phase matching in layered hyperbolic metamaterials', European Quantum Electronics Conference, Optical Society of America, Munich Germany, pp. EH_P_8-EH_P_8.
Wolff, C., Kuhlmey, B., de Sterke, C.M., Smith, M.J., Lapine, M. & Poulton, C.G. 2015, 'Artificial electrostriction in metamaterials', Proceedings of SPIE, SPIE Micro+Nano Materials, Devices, and Applications 2015, Society of Photo-optical Instrumentation Engineers (SPIE), Sydney, pp. 20-20.
Lapine, M. & Jelinek, L. 2015, 'New aspects of artificial diamagnetics', 9th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), IEEE, Oxford, UK, pp. 172-174.
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Lapine, M., Poulton, C.G. & McPhedran, R.C. 2015, 'Mesoscopic effects in discretised metamaterial spheres', SPIE Micro + Nano Materials, Devices, and Applications, International Society for Optics and Photonics, Sydney, NSW, Australia, pp. 96680L-96680L.
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Lapine, M. 2014, 'Structural tricks for enhanced metamaterial properties', 2014 8th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2014, pp. 178-180.
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© 2014 IEEE. This contribution presents an overview of novel structural approaches to the design of metamaterials, which enhance their performance by boosting emerging functionality. The two characteristic features of these approaches are hybrid assembly and finiteness effects, both providing unusual links between material properties and triggering unexpected effects. In a series of examples, the advantages of hybrid and mesoscopic designs will be demonstrated.
Krylova, A.K., Lapine, M., Poulton, C.G., McPhedran, R.C., Kivshar, Y.S., Belov, P.A. & IEEE 2013, 'Tailoring lattice parameters for broadband artificial diamagnetism', 2013 7TH INTERNATIONAL CONGRESS ON ADVANCED ELECTROMAGNETIC MATERIALS IN MICROWAVES AND OPTICS (METAMATERIALS 2013), pp. 34-36.
Lapine, M. 2013, 'Mechanical nonlinearities in electromagnetic metamaterials', 2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2013, pp. 352-354.
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We review our recent achievements in the development of metamaterials with mechanical nonlinearity. The novel nonlinearity types are achieved by enabling new degrees of freedom in metamaterial design, which allow a dynamic changes in the geometry of 'meta-atoms' or in the lattice structure. We present the outcomes of magnetoelastic, conformational, rotational and optical nonlinear feedback, and predict unusual phenomena to be observed in such metamaterials. © 2013 IEEE.
Slobozhanyuk, A.P., Kapitanova, P.V., Shadrivov, I.V., Filonov, D.S., Powell, D.A., Belov, P.A., Lapine, M. & Kivshar, Y.S. 2013, 'Light coupling in microwave metamaterials', 2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2013, pp. 190-192.
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We report our recent achievements in tuning metamaterials with light. We introduce a novel approach to design metamaterials with sign-varying nonlinear response. For this purpose, we use split-ring resonators loaded by photodiodes and varactor diodes. A non-monotonic frequency shift of the resonance frequency depending on incident microwave power is demonstrated. Finally, we show how the nonlinear response of photosensitive metamaterials can be directly controlled by light coupling. © 2013 IEEE.
Liu, M., Powell, D.A., Shadrivov, I.V., Lapine, M. & Kivshar, Y.S. 2013, 'Dynamic optical activity and self-oscillation in torsional metamaterials', 2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2013, pp. 359-360.
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We study the nonlinear dynamic properties of coupled torsional meta-molecules. We find that this structure may exhibit self-oscillation behaviour, and we analyse two different mechanisms leading to this effect. Contrary to many previously studied optomechanical systems, self-oscillations of torsional meta-molecules can be extremely robust against mechanical damping and they can be manipulated by the polarisation of electromagnetic waves. We also study the dynamic nonlinear optical activity arising in the system and its active control. © 2013 IEEE.
Liu, M., Sun, Y., Powell, D.A., Shadrivov, I.V., Lapine, M., McPhedran, R.C. & Kivshar, Y.S. 2013, 'Twists and shifts make nonlinear metamaterials', 2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, CLEO/Europe-IQEC 2013.
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Recent studies have demonstrated that it is possible to modify the properties of metamaterials by electromagnetic waves via inducing mechanical deformations of samples and therefore changing material properties. As an example, optical rotation of chiral particles was demonstrated [1], and a rich variety of nonlinear behaviour was achieved with magneto-elastic metamaterials [2] . The range of possible effects achievable in this way promises to be richer than in the prominent area of optomechanics, because the greater flexibility in metamaterial design overcomes the limits of available material functionalities, and offers wider possibilities for optimisation. At the same time, the implementation of magnetoelastic metamaterials [2] remains challenging and in some cases, such as the conformational nonlinearity in resonant spirals, remains inaccessible for optics. The reason for this is that the magnetic forces, employed in the initial designs, are relatively weak, so such materials require either high power or extremely small elastic restoring forces, which poses a considerable manufacturing challenge. We recall, however, that earlier research on structurally tunable metamaterials [3] indicated that near-field interaction may significantly improve the tunability range and leads to various effects associated with near-field coupling. © 2013 IEEE.
Slobozhanyuk, A.P., Belov, P.A., Lapine, M., McPhedran, R.C., Powell, D.A., Shadrivov, I.V. & Kivshar, Y.S. 2013, 'Novel nonlinear chiral metamaterials', IEEE Antennas and Propagation Society, AP-S International Symposium (Digest), pp. 488-489.
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We report on a novel metamaterial design based on multi-turn spiral resonators which strongly enhance nonlinear coupling between electromagnetic and mechanical response. The robust fabrication procedures allowed to produce a large number of resonators, suitable for assembling large metamaterials arrays. We experimentally demonstrate a remarkable self-tuning of the electromagnetic resonance, achieved via power-dependent mechanical reconfiguration, dominating over thermal effects. The corresponding compression of the spirals provides a nonlinear chiral response. © 2013 IEEE.
Slobozhanyuk, A.P., Kapitanova, P.V., Filonov, D.S., Belov, P.A., Shadrivov, I.V., Powell, D.A., Kivshar, Y.S. & Lapine, M. 2013, 'Photosensitive SRR-metamaterials', IEEE Antennas and Propagation Society, AP-S International Symposium (Digest), pp. 1190-1191.
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We report a novel approach to design metamaterials with sign-varying nonlinear response. The metamaterial is build up with split-ring resonators loaded by photodiodes and varactor diodes. A non-monotonic frequency shift of the resonance frequency depending on incident microwave power is demonstrated. We show how the nonlinear response of such metamaterials can be directly controlled by light. © 2013 IEEE.
Slobozhanyuk, A.P., Filonov, D.S., Lapine, M., Belov, P.A., Shadrivov, I.V., Kivshar, Y.S. & IEEE 2012, 'Nonlinear Spiral Metamaterials', 2012 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM (APSURSI).
Lapine, M., Shadrivov, I.V., Powell, D.A. & Kivshar, Y.S. 2011, 'Magnetoelastic metamaterials', 2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference, CLEO EUROPE/EQEC 2011.
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We propose and demonstrate experimentally a novel type of nonlinearity in metamaterials, which is induced by mechanical deformation of the structure. The nonlinearity arises from the introduction of an extra degree of freedom in the metamaterial, which allows for elastic displacement of the strongly interacting structural elements (see Fig. 1a). This type of nonlinearity relies on the counterplay between the electromagnetic attraction and the elastic repulsion, and the induced deformation alters the electromagnetic response of the entire structure, leading to the novel nonlinear response of the metamaterial. © 2011 IEEE.
Powell, D.A., Lapine, M., Gorkunov, M., Shadrivov, I.V. & Kivshar, Y.S. 2010, 'Metamaterial tuning using near-field interaction', Optics InfoBase Conference Papers.
We show theoretically and experimentally that by adjusting the lattice configuration we are able to manipulate the near-field interaction of resonant particles, and thus tune the response of a lattice of split-ring resonators. © 2010 Optical Society of America.
Powell, D.A., Lapine, M., Gorkunov, M., Shadrivov, I.V. & Kivshar, Y.S. 2010, 'Metamaterial tuning using near-field interaction', Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference: 2010 Laser Science to Photonic Applications, CLEO/QELS 2010.
We show theoretically and experimentally that by adjusting the lattice configuration we are able to manipulate the near-field interaction of resonant particles, and thus tune the response of a lattice of split-ring resonators. © 2010 Optical Society of America.
Lapine, M., Powell, D., Gorkunov, M., Shadrivov, I. & Kivshar, Y. 2010, 'Tuning methods for metamaterials', Proceedings of SPIE - The International Society for Optical Engineering.
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We discuss a novel tuning method based on continuous adjustment of metamaterial lattice parameters. This method provides for remarkable tuning of transmission characteristics through a subtle displacement of metamaterial layers. While the effective medium theory predicts correctly the general tuning characteristics, it turns out that the particular tuning pattern is determined by the peculiarities of near-field interaction between the metamaterial elements. We describe the modes of this interaction and provide qualitative explanations to the performance observed numerically and experimentally. © 2010 SPIE.
Powell, D.A., Lapine, M., Gorkunov, M., Shadrivov, I.V. & Kivshar, Y.S. 2010, 'Analysing and manipulating near-field interaction in metamaterials', Proceedings - 2010 12th International Conference on Electromagnetics in Advanced Applications, ICEAA'10, pp. 87-88.
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The complex near-field interactions in metamaterials provide a unique opportunity to tailor their response by modifying the lattice structure. We show that a lateral offset between the layers of rings provides a convenient tuning mechanism, and how the frequency tuning can be easily predicted from the charge distribution of a single ring at resonance. ©2010 IEEE.
Algarín, J.M., Freire, M.J., Lapine, M. & Marqués, R. 2010, 'Ab initio experimental analysis of realistic resonant ring metamaterial lenses', 2010 IEEE International Symposium on Antennas and Propagation and CNC-USNC/URSI Radio Science Meeting - Leading the Wave, AP-S/URSI 2010.
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Metamaterials - artificial composites having emergent properties not available in Nature - became a subject of interest for the scientific community after the first experimental demonstration of an artificial medium with simultaneously negative and [1]. Among their most important novel applications was the possibility of fabricating a super-lens with sub-wavelenght resolution [2] . Actually, it was soon recognized that this effect is severely restricted by the losses and the discrete nature. Analysis of losses leads to a well known formula for the minimum resolution of the lens (see, for instance, [3] and references therein) © 2010 IEEE.
Lapine, M., Nefedov, I.S., Säily, J. & Tretyakov, S.A. 2007, 'Artificial lines with exotic dispersion for phase shifters and delay lines', Proceedings of the 36th European Microwave Conference, EuMC 2006, pp. 427-430.
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We discuss various possibilities to design phase shifters with reduced frequency dispersion using combined sections of forward-wave and backward-wave transmission lines. It is shown that inclusion of backward-wave sections into a single transmission line always increases the total dispersion. On the other hand, we show that dispersion can be reduced by means of lines with positive anomalous dispersion and provide an example of such line. Furthermore, we report the theory and design of a novel phase shifter, based on parallel combined backward-forward transmission lines. The phase shifts, produced by this device, are characterized with negligible frequency dependence in a wide frequency range. We show that for an ideal performance, phase deviation can be less than 1° within a 20% bandwidth while excellent impedance matching is retained. We support these theoretical estimates by microwave circuit simulations and direct measurements, showing that the novel phase shifter can be easily implemented with simple electronic components. © 2006 EuMA.
Mynttinen, T., Lapine, M., Säily, J., Nefedov, I.S. & Tretyakov, S.A. 2006, 'Microwave devices with enhanced phase-compensation principle', European Space Agency, (Special Publication) ESA SP.
We report an advanced phase compensation principle, which employs combined backward-forward transmission lines having similar frequency dispersion. Various applications of this principle to the design of microwave devices allow for an exceptionally low dispersion in a wide frequency range while keeping the structure very compact and simple compared to conventional solutions. To illustrate the idea, we present the performance of (i) phase shifters, (ii) power dividers and (iii) baluns (complete antenna feeders) built on the reported principle. We support the theoretical estimates by microwave circuit simulations and direct measurements, showing that the novel devices can be easily implemented with simple electronic components.

Journal articles

Lapine, M. 2017, 'New degrees of freedom in nonlinear metamaterials', Physica Status Solidi (B) Basic Research, vol. 254, no. 4.
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© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim This is an overview of the recent achievements in exploiting novel degrees of freedom in metamaterial design, which enable sophisticated nonlinear coupling mechanisms and bring enhancement to nonlinear behavior. One of the novel paradigms makes use of mechanical feedback, achieved by embedding electromagnetic resonators within elastic medium or engineering explicit elastic links between them, such as rotational feedback. These designs provide broad-band self-adjustable resonances, self-oscillations, chaotic regimes, nonlinear chirality and, spontaneous chiral symmetry breaking. With this respect, a range of implementations has been analyzed, from flexible helices for microwaves to artificial electrostriction in optics. Another concept benefits from multi-frequency operation, where the properties in completely distinct frequency ranges become entangled through specific metamaterial design –for example, direct optical coupling can be introduced between microwave resonators, providing an independent interaction channel. It was also found that hyperbolic metamaterials can bring notable benefits to classical nonlinear processes by imposing unusual phase matching solutions, with a rich choice of matching combinations. Finally, the boundary structure of metamaterials add yet another possibility to control their properties. Overall, the recent progress in these topics suggests a very positive outlook into the future of nonlinear metamaterials.
Gorlach, M.A., Voytova, T.A., Lapine, M., Kivshar, Y.S. & Belov, P.A. 2016, 'Nonlocal homogenization for nonlinear metamaterials', PHYSICAL REVIEW B, vol. 93, no. 16.
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Smith, M.J.A., Kuhlmey, B.T., De Sterke, C.M., Wolff, C., Lapine, M. & Poulton, C.G. 2016, 'Metamaterial control of stimulated Brillouin scattering', Optics Letters, vol. 41, no. 10, pp. 2338-2341.
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© 2016 Optical Society of America. Using full opto-acoustic numerical simulations, we demonstrate enhancement and suppression of the SBS gain in a metamaterial comprising a subwavelength cubic array of dielectric spheres suspended in a dielectric background material. We develop a general theoretical framework and present several numerical examples using technologically important materials. For As 2 S 3 spheres in silicon, we achieve a gain enhancement of more than an order of magnitude compared to pure silicon and for GaAs spheres in silicon, full suppression is obtained. The gain for As 2 S 3 glass can also be strongly suppressed by embedding silica spheres. The constituent terms of the gain coefficient are shown to depend in a complex way on the filling fraction. We find that electrostriction is the dominant effect behind the control of SBS in bulk media.
Lapine, M., McPhedran, R.C. & Poulton, C.G. 2016, 'Slow convergence to effective medium in finite discrete metamaterials', Physical Review B, vol. 93, no. 23.
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© 2016 American Physical Society. It is known that metamaterial properties may differ significantly from the predictions of effective-medium theory. In many cases this is due to the finite size and discrete structure, which cannot be neglected in practical samples with a relatively small amount of elements. We analyze the response of finite discrete metamaterial objects of a spherical shape and demonstrate the role of boundary effects in these structures, pointing out an interplay between the size of the structure and the dissipation. We conclude that the discrepancy between the actual resonance frequency of a sphere and the effective-medium prediction is inversely proportional to the size of the sphere.
Smith, M.J.A., Wolff, C., de Sterke, C.M., Lapine, M., Kuhlmey, B.T. & Poulton, C.G. 2016, 'Stimulated Brillouin scattering in metamaterials', Journal of the Optical Society of America B, vol. 33, no. 10, pp. 2162-2162.
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Smith, M.J.A., Wolff, C., De Sterke, C.M., Lapine, M., Kuhlmey, B.T. & Poulton, C.G. 2016, 'Stimulated Brillouin scattering enhancement in silicon inverse opal waveguides', Optics Express, vol. 24, no. 22, pp. 25148-25148.
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Duncan, C., Perret, L., Palomba, S., Lapine, M., Kuhlmey, B.T. & de Sterke, C.M. 2015, 'New avenues for phase matching in nonlinear hyperbolic metamaterials', SCIENTIFIC REPORTS, vol. 5.
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Smith, M.J.A., Kuhlmey, B.T., De Sterke, C.M., Wolff, C., Lapine, M. & Poulton, C.G. 2015, 'Electrostriction enhancement in metamaterials', Physical Review B - Condensed Matter and Materials Physics, vol. 91, no. 21.
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© 2015 American Physical Society. We demonstrate a controllable enhancement in the electrostrictive properties of a medium using dilute composite artificial materials. Analytical expressions for the composite electrostriction are derived and used to show that enhancement, tunability, and suppression can be achieved through a careful choice of constituent materials. Numerical examples with Ag, As2S3, Si, and SiO2 demonstrate that even in a nonresonant regime, artificial materials can bring more than a threefold enhancement in the electrostriction.
Liu, M., Powell, D., Shadrivov, I., Kivshar, Y. & Lapine, M. 2014, 'Chiral torsional metamaterials', Optics and Photonics News, vol. 25, no. 12, p. 51.
Jelinek, L., Lapine, M. & McPhedran, R.C. 2014, 'Applicability of nonresonant artificial diamagnetics', PHYSICAL REVIEW B, vol. 90, no. 10.
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Lapine, M., Shadrivov, I.V. & Kivshar, Y.S. 2014, 'Colloquium: Nonlinear metamaterials', Reviews of Modern Physics, vol. 86, no. 3.
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© 2014 American Physical Society. This Colloquium presents an overview of the research on nonlinear electromagnetic metamaterials. The developed theoretical approaches and experimental designs are summarized, along with a systematic description of various phenomena available with nonlinear metamaterials.
Liu, M., Powell, D.A., Shadrivov, I.V., Lapine, M. & Kivshar, Y.S. 2014, 'Spontaneous chiral symmetry breaking in metamaterials', Nature Communications, vol. 5.
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Spontaneous chiral symmetry breaking underpins a variety of areas such as subatomic physics and biochemistry, and leads to an impressive range of fundamental phenomena. Here we show that this prominent effect is now available in artificial electromagnetic systems, enabled by the advent of magnetoelastic metamaterials where a mechanical degree of freedom leads to a rich variety of strong nonlinear effects such as bistability and self-oscillations. We report spontaneous symmetry breaking in torsional chiral magnetoelastic structures where two or more meta-molecules with opposite handedness are electromagnetically coupled, modifying the system stability. Importantly, we show that chiral symmetry breaking can be found in the stationary response of the system, and the effect is successfully demonstrated in a microwave pump-probe experiment. Such symmetry breaking can lead to a giant nonlinear polarization change, energy localization and mode splitting, which provides a new possibility for creating an artificial phase transition in metamaterials, analogous to that in ferrimagnetic domains. © 2014 Macmillan Publishers Limited.
Slobozhanyuk, A.P., Kapitanova, P.V., Filonov, D.S., Powell, D.A., Shadrivov, I.V., Lapine, M., Belov, P.A., McPhedran, R.C. & Kivshar, Y.S. 2014, 'Nonlinear interaction of meta-atoms through optical coupling', APPLIED PHYSICS LETTERS, vol. 104, no. 1.
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Lapine, M., Krylova, A., Belov, P., Poulton, C.G., McPhedran, R.C. & Kivshar, Y. 2013, 'Broadband Diamagnetism In Anisotropic Metamaterials', Physical Review B, vol. 87, no. 2, pp. 1-7.
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We discuss the strategy for achieving the values of the effective magnetic permeability much smaller than unity by employing an appropriate arrangement of metamaterial elements (meta-atoms). We demonstrate that strong diamagnetism over a very wide frequency range can be realized in metamaterials by employing nonresonant elements with deeply subwavelength dimensions. We analyze the effect of the lattice parameters on the diamagnetic response and find that selecting an appropriate lattice type is crucial for optimal performance. Finally, we discuss the optimal characteristics required to obtain the lowest possible values of magnetic permeability and point out an efficient tuning possibility.
Belov, P.A., Slobozhanyuk, A.P., Filonov, D.S., Yagupov, I.V., Kapitanova, P.V., Simovski, C.R., Lapine, M. & Kivshar, Y.S. 2013, 'Broadband isotropic mu-near-zero metamaterials', APPLIED PHYSICS LETTERS, vol. 103, no. 21.
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Liu, M., Powell, D.A., Shadrivov, I.V., Lapine, M. & Kivshar, Y.S. 2013, 'Self-oscillations in nonlinear torsional metamaterials', New Journal of Physics, vol. 15.
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We study the nonlinear dynamics of torsional meta-molecules - sub-wavelength resonators with strong coupling between electromagnetic excitation and rotational deformation - and show that such structures may undergo self-oscillations. We develop a semi-analytical model to evaluate the electromagnetic-elastic coupling in such structures. By analysing the local stability of the system, we reveal two different mechanisms leading to self-oscillations. Contrary to many previously studied optomechanical systems, self-oscillations of torsional meta-molecules can be extremely robust against mechanical damping. Due to the chiral nature of the structure, a consequence of self-oscillations in this system is dynamic nonlinear optical activity, which can be actively controlled by a range of parameters such as the field strength and polarization of the incident wave. © IOP Publishing and Deutsche Physikalische Gesellschaft.
Liu, M., Sun, Y., Powell, D.A., Shadrivov, I.V., Lapine, M., McPhedran, R.C. & Kivshar, Y.S. 2013, 'Nonlinear response via intrinsic rotation in metamaterials', Physical Review B - Condensed Matter and Materials Physics, vol. 87, no. 23.
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We propose and experimentally verify a way to achieve strong nonlinear coupling between the electromagnetic and elastic properties in metamaterials. This coupling is provided through a novel degree of freedom in metamaterial design: the internal rotation within structural elements. Our meta-atoms have high sensitivity to electromagnetic wave power, and the elastic and electromagnetic properties can be independently designed to optimize the response. We demonstrate a rich range of nonlinear phenomena including self-tuning and bistability, and provide a comprehensive experimental demonstration of the predicted effects. © 2013 American Physical Society.
Slobozhanyuk, A.P., Lapine, M., Powell, D.A., Shadrivov, I.V., Kivshar, Y.S., McPhedran, R.C. & Belov, P.A. 2013, 'Flexible Helices for Nonlinear Metamaterials', ADVANCED MATERIALS, vol. 25, no. 25, pp. 3409-3412.
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Noginov, M., Lapine, M., Podolskiy, V. & Kivshar, Y. 2013, 'Focus issue: hyperbolic metamaterials.', Optics express, vol. 21, no. 12, pp. 14895-14897.
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This special issue presents a cross-section of recent progress in the rapidly developing area of optics of hyperbolic metamaterials.
Lapine, M., Jelinek, L. & Marqués, R. 2012, 'Surface mesoscopic effects in finite metamaterials', Optics Express, vol. 20, no. 16, pp. 18297-18302.
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While the effective medium treatment of unbounded metamaterials appears to be well established and firmly proven, related phenomena in finite structures have not received sufficient attention. We report on mesoscopic effects associated with the boundaries of finite discrete metamaterial samples, which can invalidate an effective medium description. We show how to avoid such effects by proper choice of boundary configuration. As all metamaterial implementations are naturally finite, we are confident that our findings are crucial for future metamaterial research. © 2012 Optical Society of America.
Lapine, M., Shadrivov, I. & Kivshar, Y. 2012, 'Wide-band negative permeability of nonlinear metamaterials.', Scientific reports, vol. 2, pp. 1-4.
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We propose a novel way to achieve an exceptionally wide frequency range where metamaterial possesses negative effective permeability. This can be achieved by employing a nonlinear response of metamaterials. We demonstrate that, with an appropriate design, a frequency band exceeding 100% is available for a range of signal amplitudes. Our proposal provides a significant improvement over the linear approach, opening a road towards broadband negative refraction and its applications.
Lapine, M., Shadrivov, I.V., Powell, D.A. & Kivshar, Y.S. 2012, 'Magnetoelastic metamaterials', Nature Materials, vol. 11, no. 1, pp. 30-33.
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The study of advanced artificial electromagnetic materials, known as metamaterials, provides a link from material science to theoretical and applied electrodynamics, as well as to electrical engineering. Being initially intended mainly to achieve negative refraction, the concept of metamaterials quickly covered a much broader range of applications, from microwaves to optics and even acoustics. In particular, nonlinear metamaterials established a new research direction giving rise to fruitful ideas for tunable and active artificial materials. Here we introduce the concept of magnetoelastic metamaterials, where a new type of nonlinear response emerges from mutual interaction. This is achieved by providing a mechanical degree of freedom so that the electromagnetic interaction in the metamaterial lattice is coupled to elastic interaction. This enables the electromagnetically induced forces to change the metamaterial structure, dynamically tuning its effective properties. This concept leads to a new generation of metamaterials, and can be compared to such fundamental concepts of modern physics as optomechanics of photonic structures or magnetoelasticity in magnetic materials.
Lapine, M., Shadrivov, I.V., Powell, D.A. & Kivshar, Y.S. 2011, 'Metamaterials with conformational nonlinearity', SCIENTIFIC REPORTS, vol. 1.
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Marqués, R., Jelinek, L., Freire, M.J., Baena, J.D. & Lapine, M. 2011, 'Bulk metamaterials made of resonant rings', Proceedings of the IEEE, vol. 99, no. 10, pp. 1660-1668.
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In this brief review, we present the fundamentals of bulk resonant ring metamaterial (RRM) theory. Metamaterials made of resonant rings are discussed, and some basic design rules are provided. Homogenization (including spatial dispersion) of 3-D resonant ring latices is reviewed, with emphasis in isotropic designs. Edge effects in finite size metamaterial samples are discussed. Finally, possible applications and future trends are briefly reviewed. © 2011 IEEE.
Boardman, A.D., Grimalsky, V.V., Kivshar, Y.S., Koshevaya, S.V., Lapine, M., Litchinitser, N.M., Malnev, V.N., Noginov, M., Rapoport, Y.G. & Shalaev, V.M. 2011, 'Active and tunable metamaterials', Laser and Photonics Reviews, vol. 5, no. 2, pp. 287-307.
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Metamaterial research is an extremely important global activity that promises to change our lives in many different ways. These include making objects invisible and the dramatic impact of metamaterials upon the energy and medical sectors of society. Behind all of the applications, however, lies the business of creating metamaterials that are not going to be crippled by the kind of loss that is naturally heralded by use of resonant responses in their construction. This review sets out some solutions to the management of loss and gain, coupled to controlled and nonlinear behavior, and discusses some critical consequences concerning stability. Under the general heading of active and tunable metamaterials, an international spectrum of authors collaborates here to present a set of solutions that addresses these issues in several directions. As will be appreciated, the range of possible solutions is really fascinating, and it is hoped that these discussions will act as a further stimulus to the field. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Algarin, J.M., Freire, M.J., Lopez, M.A., Lapine, M., Jakob, P.M., Behr, V.C. & Marqús, R. 2011, 'Analysis of the resolution of split-ring metamaterial lenses with application in parallel magnetic resonance imaging', Applied Physics Letters, vol. 98, no. 1.
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In this work, we experimentally determine the resolution of split-ring metamaterials lenses with emphasis in magnetic resonance imaging applications. Two small sources are used to determine the minimal resolution of the lens, which is compared with previous theoretical predictions. Taking into account this minimal resolution, a second experiment is designed in order to study the ability of a split-ring lens to improve the localization of the field produced by two closely spaced coils. This ability could find application in parallel magnetic resonance imaging, which take advantage of the distinct coil sensitivities in order to reduce the image acquisition time. © 2011 American Institute of Physics.
Lapine, M., Jelinek, L., Freire, M.J. & Marqués, R. 2010, 'Realistic metamaterial lenses: Limitations imposed by discrete structure', Physical Review B - Condensed Matter and Materials Physics, vol. 82, no. 16.
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We study the peculiarities of a metamaterial "superlens," caused by its discrete structure and finite size. We show that precise modeling of the lens provides remarkable distinctions from continuous medium approximation. In particular, we address the problem of highest resolution that can be achieved with a realistic electrically thin metamaterial lens. We conclude that discrete structure imposes essential limitations on the resolution and that the resolution cannot be improved by decreasing dissipation in the system. Further implications related to effective medium description of discrete structures are discussed. © 2010 The American Physical Society.
Powell, D.A., Lapine, M., Gorkunov, M.V., Shadrivov, I.V. & Kivshar, Y.S. 2010, 'Metamaterial tuning by manipulation of near-field interaction', Physical Review B - Condensed Matter and Materials Physics, vol. 82, no. 15.
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We analyze the near-field interaction between the resonant subwavelength elements of a metamaterial and present a method to calculate the electric and magnetic interaction coefficients. We show that by adjusting the relative configuration of the neighboring split ring resonators it becomes possible to manipulate this near-field interaction, and thus tune the response of metamaterials. We use the results of this analysis to explain the experimentally observed tuning of microwave metamaterials. © 2010 The American Physical Society.
Lapine, M., Jelinek, L., Marqués, R. & Freire, M.J. 2010, 'Exact modelling method for discrete finite metamaterial lens', IET Microwaves, Antennas and Propagation, vol. 4, no. 8, pp. 1132-1139.
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The authors analyse the properties of metamaterial lens composed of capacitively loaded ring resonators, with the help of an efficient rigorous model suitable for calculating the properties of finite metamaterial samples. This approach takes into account the discrete structure and finite extent of realistic metamaterials. The authors show that the discrete model reveals the effects, which can be missed by a continuous model based on effective parameters and that the results are in close agreement with the experimental data. © 2010 The Institution of Engineering and Technology.
Minovich, A., Neshev, D.N., Powell, D.A., Shadrivov, I.V., Lapine, M., McKerracher, I., Hattori, H.T., Tan, H.H., Jagadish, C. & Kivshar, Y.S. 2010, 'Tilted response of fishnet metamaterials at near-infrared optical wavelengths', Physical Review B - Condensed Matter and Materials Physics, vol. 81, no. 11.
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We study experimentally the transmission properties of Au-TiO2 -Au fishnet metamaterials in the near-infrared spectral range and analyze the change in the transmission resonances at varying angles of incidence and different input polarizations. The results show that the main transmission peak through the fishnet is due to the excitation of hole modes. This high-transmission region is significantly influenced by surface plasmon coupling when the incident electric field has a component normal to the metal plates, while little change with respect to tilt is observed when the electric field is parallel to the two metal films of the fishnet. © 2010 The American Physical Society.
Freire, M.J., Jelinek, L., Marques, R. & Lapine, M. 2010, 'On the applications of micror=-1 metamaterial lenses for magnetic resonance imaging.', Journal of magnetic resonance (San Diego, Calif. : 1997), vol. 203, no. 1, pp. 81-90.
In this work some possible applications of negative permeability magnetic metamaterial lenses for magnetic resonance imaging (MRI) are analyzed. It is shown that using magnetic metamaterials lenses it is possible to manipulate the spatial distribution of the radio-frequency (RF) field used in MR systems and, under some circumstances, improve the sensitivity of surface coils. Furthermore a collimation of the RF field, phenomenon that may find application in parallel imaging, is presented. MR images of real tissues are shown in order to prove the suitability of the theoretical analysis for practical applications.
Lapine, M. 2009, 'Tunable metamaterials: the key step to practical application', SPIE Newsroom.
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Lapine, M., Powell, D., Gorkunov, M., Shadrivov, I., Marqús, R. & Kivshar, Y. 2009, 'Structural tunability in metamaterials', Applied Physics Letters, vol. 95, no. 8.
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We propose an efficient approach for tuning the transmission characteristics of metamaterials through a continuous adjustment of the lattice structure and confirm it experimentally in the microwave range. The concept is rather general and applicable to various metamaterials as long as the effective medium description is valid. The demonstrated continuous tuning of a metamaterial response is highly desirable for a number of emerging applications of metamaterials, including sensors, filters, and switches, realizable in a wide frequency range. © 2009 American Institute of Physics.
Sihvola, A. & Lapine, M. 2008, 'Editorial', Metamaterials, vol. 2, no. 2-3, p. 53.
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Lapine, M. 2007, 'The Age of Metamaterials', Metamaterials, vol. 1, no. 1, p. 1.
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Lapine, M. & Tretyakov, S. 2007, 'Contemporary notes on metamaterials', IET Microwaves, Antennas and Propagation, vol. 1, no. 1, pp. 3-11.
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The essence of the metamaterial concept from the structural point of view. Particular attention is paid to the macroscopic description of metamaterials and to the corresponding requirements and precautions for using that concept. General advantages of metamaterials are also pointed out. Next, the main research directions related to metamaterials are briefly overviewed and the key references are provided. Finally, the most probable sources of disagreement and misunderstanding within the field are summarised. © 2007 The Institution of Engineering and Technology.
Lapine, M. & Tretyakov, S. 2007, 'Contemporary notes on metamaterials', IET MICROWAVES ANTENNAS & PROPAGATION, vol. 1, no. 1, pp. 3-11.
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Gorkunov, M.V., Lapine, M.V. & Tretyakov, S.A. 2006, 'Methods of crystal optics for studying electromagnetic phenomena in metamaterials: Review', Crystallography Reports, vol. 51, no. 6, pp. 1048-1062.
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The state of the art of electrodynamics of new composite media-metamaterials-is reviewed. The composites in the form of a periodic lattice of identical elements, which are in essence artificial crystals with characteristic scales of the internal structure from several centimeters to several hundred nanometers are considered. The most important properties of metamaterials and the specific features of propagation of electromagnetic signals in these media are described. Particular attention is paid to the conventional methods of condensed-matter physics, which have found application in the electrodynamics of metamaterials and have provided dynamic development of this new field of science and technology. © Nauka/Interperiodica 2006.
Ikonen, P., Lapine, M., Nefedov, I. & Tretyakov, S. 2006, 'Vector circuit theory for spatially dispersive uniaxial magneto-dielectric slabs', Progress in Electromagnetics Research, vol. 63, pp. 279-294.
We present a general dyadic vector circuit formalism, applicable for uniaxial magneto-dielectric slabs, with strong spatial dispersion explicitly taken into account. This formalism extends the vector circuit theory, previously introduced only for isotropic and chiral slabs. Here we assume that the problem geometry imposes strong spatial dispersion only in the plane, parallel to the slab interfaces. The difference arising from taking into account spatial dispersion along the normal to the interface is briefly discussed. We derive general dyadic impedance and admittance matrices, and calculate corresponding transmission and reflection coefficients for arbitrary plane wave incidence. As a practical example, we consider a metamaterial slab built of conducting wires and split-ring resonators, and show that neglecting spatial dispersion and uniaxial nature in this structure leads to dramatic errors in calculation of transmission characteristics.
Lapine, M. & Gorkunov, M. 2004, 'Three-wave coupling of microwaves in metamaterial with nonlinear resonant conductive elements', Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, vol. 70, no. 6 2.
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A metamaterial processing nonlinear magnetic response owing to nonlinear electronic components inserted into resonant conductive elements was considered. An approach for analyzing three-wave coupling processes with a strong pump wave and two weak signals was developed. The pecularities of coupling arising from use of insertions with variable resistance or variable capacitance were discussed. It was estimated that extremely strong nonlinear coupling can be achieved using typical diodes.
Gorkunov, M. & Lapine, M. 2004, 'Tuning of a nonlinear metamaterial band gap by an external magnetic field', Physical Review B - Condensed Matter and Materials Physics, vol. 70, no. 23, pp. 1-9.
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We consider tuning of permeability of a nonlinear metamaterial with resonant conductive elements by an external varying magnetic field. We propose two tuning regimes: slow tuning, when the permeability follows adiabatically the field variations, and high-frequency tuning, when changes of the pump microwave amplitude and/or frequency affect the permeability. We demonstrate how the metamaterial band gap can be tuned and describe the resulting metamaterial switching between transmitting, reflecting, and absorbing states. The details appear to depend drastically on the type of nonlinear components inserted into the resonant conductive elements. We perform practical estimates for typical diodes available for the microwave frequency range. We predict that the transmittance of a metamaterial slab can be modulated by several orders of magnitude already using a slab with thickness equal to one microwave wavelength in vacuum.
Lapine, M., Gorkunov, M. & Ringhofer, K.H. 2003, 'Nonlinearity of a metamaterial arising from diode insertions into resonant conductive elements', Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, vol. 67, no. 6 2.
It was demonstrated that with the help of simple electronic components, it was possible to construct a metamaterial which possesses nonlinear response. It was shown how the macroscopic properties of this material can be controlled by the characteristics of the structure elements, their arrangement, and the properties of nonlinear insertions. Thus, various processes known in nonlinear optics may be performed in the microwave range with the help of the proposed metamaterial.
Gorkunov, M., Lapine, M., Shamonina, E. & Ringhofer, K.H. 2002, 'Effective magnetic properties of a composite material with circular conductive elements', European Physical Journal B, vol. 28, no. 3, pp. 263-269.
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Effective magnetic properties of a composite meta-material consisting of periodically arranged circular conductive elements are studied theoretically. A general expression for the effective bulk permeability is obtained with mutual effects and lattice ordering being taken into account. The resonance frequency of the permeability is found to be strongly dependent on the size and shape of the unit cell. Frequency dispersion of the permeability is studied with special attention paid to the frequency range, where negative values of the permeability are possible. Corresponding recommendations for optimisation of the meta-materials with negative permeability are made. The results are confirmed by numerical simulations of the finite structure behaviour in an external magnetic field.
Trissl, H.W., Bernhardt, K. & Lapin, M. 2001, 'Evidence for protein dielectric relaxations in reaction centers associated with the primary charge separation detected from Rhodospirillum rubrum chromatophores by combined photovoltage and absorption measurements in the 1-15 ns time range.', Biochemistry, vol. 40, no. 17, pp. 5290-5298.
Fast photovoltage measurements in Rhodospirillum rubrum chromatophores in the nanosecond time range, escorted by time-resolved absorption measurements, are described. Under reducing conditions, the photovoltage decayed significantly faster than the spectroscopically detected charge recombination of the radical pair P(+)H(A)(-). This indicates the occurrence of considerable dielectric relaxations. Our data and data from the literature were analyzed by means of a reaction scheme consisting of three states, namely, A, P, and P(+)H(A)(-). A time-dependent DeltaG(t) was introduced by assuming a time-dependent rate constant of the back-reaction, k(-1)(t). With the exception of the latter rate constant, all other parameters of the model are reliably known within narrow limits. This allowed us to distinguish between the three cases assumed for DeltaG degrees (t): (1)DeltaG degrees (t) = constant; (2)DeltaG degrees (t) as published by Peloquin et al. [Peloquin, J. M., Williams, J. C., Lin, X. M., Alden, R. G., Taguchi, A. K. W., Allen, J. P., and Woodbury, N. W. (1994) Biochemistry 33, 8089-8100]; and a (3)DeltaG degrees (t) that fits the present data. The assumption that (1)DeltaG degrees (t) = constant is incompatible with our photovoltage data, and (2)DeltaG degrees (t) is incompatible with the constraint that the ratio of fluorescence yields in the closed and open state is F(m)/F(o) approximately 2. We specify a (3)DeltaG degrees (t) that should be valid for photosynthetic reaction centers in vivo. Furthermore, the overall kinetics of the electric relaxation, e(t), in response to the primary charge separation were determined.
Krasinskaya, I.P., Lapin, M.V. & Yaguzhinsky, L.S. 1998, 'Detection of the local H+ gradients on the internal mitochondrial membrane.', FEBS letters, vol. 440, no. 1-2, pp. 223-225.
Respiration-dependent responses of a pH probe (fluorescein isothiocyanate, FITC), covalently bound to the membrane proteins of mitochondria and submitochondrial particles (SMP) have been studied. A spectral shift indicating FITC deprotonation was observed when respiration was activated in coupled mitochondria. Such a response was increased by valinomycin and reduced by uncoupler. Some FITC deprotonation was detected in the presence of excess of an uncoupler, but the response was smaller and insensitive to valinomycin. FITC deprotonation was also observed in submitochondrial particles after succinate addition. In this case it was not affected by uncoupler. Increase in the buffer concentration was found to (i) decrease the FITC response and (ii) increase the rate of uncoupled respiration in both mitochondria and submitochondrial particles. The results are consistent with the assumption that respiration initiates appearance of local H+ activity gradients on the inner side of the internal mitochondrial membrane during the steady-state H+ pumping. We suggest that the formation of this gradient is due to kinetic barrier to proton transfer from the bulk phase to the respiratory proton pump vicinity.