Mikael C. Rechtsman mcr at technion dot ac dot il  Technion - Israel Institute of Technology
Physics Department
Haifa, Israel 32000
+972 50 597 5787
Education
Princeton University, Ph.D. (2003-2008)
Massachusetts Institute of Technology, S.B. (2000-2003)
Research Interests: Linear and nonlinear Complex Photonic Structures Effective magnetism at optical frequencies Magnetic effects at optical frequencies at the nano and microscales have been treated as essentially negligible for the history of the field, due to weak coupling to atomic magnetic dipoles. In a recent theoretical and experimental study [see #17 below], we have found a way to overcome this barrier by generating large effective magnetic fields in optical graphene (see below) via an inhomogeneous strain in the system. This allows us to probe the effects of magnetism in photonic structures, including the existence of Landau levels, spectral band gaps that open up between Landau levels, and quantum-Hall type edge states. The collapsing of photonic states into highly degenerate Landau levels suggests applications in enhancement and suppression of spontaneous emission (with potential use in LEDs, semiconductor lasers, and other applications). From a fundamental point of view, the existence of an effective magnetic field begs the question of the extent to which topological protection can be achieved in optics (as it is in topological insulators in condensed matter systems) in order to achieve complete robustness against fabrication imperfections. Honeycomb lattices: "optical graphene" A waveguide array arranged in a honeycomb lattice obeys essentially the same equations as do electrons in graphene (hence we call this structure "optical graphene"). The key physical characteristic here is the "Dirac regions" - the parts of the spectrum where light obeys the massless Dirac equation (linear dispersion), rather than a quadratic dispersion. The linear dispersion changes everything: the phenomenon of Klein tunneling means that light can cross a barrier without any backscattering whatsoever, and means robustness against structural disorder; another example is the nature of the edge states, which have completely flat bands (i.e., they're dispersionless), thus allowing supercollimated light to travel unchanged over large distances [see #16 below]. While we use photonic lattices (a.k.a. waveguide arrays) to probe this system, Dirac points exist across many platforms, including photonic crystals, photonic crystal fibers, and optical lattices. At the heart of the bizarre physics of graphene lie deep notions of topology (non-trivial Berry's phase) and symmetry (conservation of pseudospin), that have yet to be put to use in photonics. Band gaps in amorphous photonic crystals for soft matter A holy grail of soft condensed matter physics is finding a self-assembling structure that has a complete photonic band gap, especially at low dielectric contrast ratios (since nearly all soft matter systems have components with dielectric constants in the area of 1.2-2.0). The realization of a self-assembling photonic band gap system would combine all the striking technological possibilities of nanophotonics to cheaply made and extremely scalable soft systems (like nano-scale colloids). At low dielectric contrasts, periodic crystals typically do a bad job of opening a band gap. In present work, we ask the question: can disordered systems open large photonic band gaps at low contrast? (see [12] below - the answer is yes) What is the nature of the disorder that does this best? How do we implement this in real colloidal systems? Photonic quasicrystals Quasicrystals are structures that, despite their total lack of periodicity, contain long-range rotational order. Quasicrystals can have five-fold rotational symmetry, which is completely forbidden to ordinary periodic crystals. Because of their highly isotropic quasi-Brillouin zone, they are excellent candidates for low-dielectric-contrast photonic band gap materials. One amazing property of quasicrystals is the fact that when you make them more messy (i.e., add disorder), waves travel more quickly and easily through them (whether these waves describe light, electrons, or lattice vibrations). We demonstrated this effect for the first time see [13] below using an optical system - an induced photorefractive lattice. Many questions about the optical properties of quasicrystals still remain, such as: what are the properties of solitons that bifurcate from their fractal eigenstates? What is the nature of their edge states? ... Negative radiation pressure Is it possible to pull particles with light - that is, to make a tractor beam? We have proposed a slab-waveguide structure made of birefringent materials that has "negative modes" that act to pull particles with light using simple radiation pressure (see [15] below). The negative modes act much like metamaterials - that is, their phase and group velocities point in opposite directions - except they are just composed of pure dielectrics, so they're in principle free of loss! Publications 18. Observation of magnetically induced band gaps in between Landau levels in photonic structures, MC Rechtsman, JM Zeuner, M Segev, A Szameit (in preparation) 17. Observation of diffraction-free edge states in optical graphene, MC Rechtsman*, Y Plotnik*, M Segev, D Song, Z Chen (in preparation) 16. Negative radiation pressure and negative effective refractive index via dielectric birefringence, J Nemirovsky, MC Rechtsman, M Segev, Optics Express 20, 8, 8907-8914 (2012). - To be featured in Nature Photonics' News and Views section 15. Negative coupling between defects in waveguide arrays, JM Zeuner, MC Rechtsman, R. Keil, F Dreisow, A Tünnermann, S Nolte, A Szameit, Opt. Lett. 37, 533-535 (2012). 14. Negative Goos-Hanchen shift in periodic media, MC Rechtsman, YV Kartashov, F Setzpfandt, H Trompeter, L Torner, T Pertsch, U Peschel, A Szameit, Negative Goos-Hanchen shift in Periodic Media, Opt. Lett. (in press). 13. Disorder-enhanced transport in photonic quasicrystals, L Levi*, MC Rechtsman*, T Schwartz, O Manela, B Freedman, M Segev, Science, 332, 1541 (2011) [*equal contribution] - See Nature Photonics News and Views article (by Z. V. Vardeny and A. Vahata) on this article. - Selected to be featured in Optics and Photonics news' "Optics in 2011" issue (forthcoming).
12. Amorphous photonic lattices: band gaps, effective mass, and suppressed transport, MC Rechtsman, A Szameit, Felix Dreisow, Matthias Heinrich, Robert Keil, Stefan Nolte, M Segev, Phys. Rev. Lett. 106, 193904 (2011) 11. PT-symmetry in honeycomb photonic lattices, A Szameit, MC Rechtsman, O Bahat-Treidel, M Segev, Phys. Rev. A (Rapid Comm) 84, 021806(R) (2011). 10. Method for obtaining upper bounds on photonic band gaps, MC Rechtsman, S Torquato, Phys. Rev. B 80, 155126 (2009).
9. Negative Poisson's Ratio Materials via Isotropic Interactions, MC Rechtsman, FH Stillinger, S Torquato, Phys. Rev. Lett. 101, 085501 (2008)
8. Optimized Structures for Photonic Quasicrystals, MC Rechtsman, HC Jeong, S Torquato, P Chaikin, PJ Steinhardt, Phys. Rev. Lett. 101, 073902 (2008) 7. Effective dielectric tensor for electromagnetic wave propagation in random media, MC Rechtsman, S Torquato, J. Appl. Phys. 103, 084901 (2008) 6. Negative thermal expansion behavior in isotropic systems, MC Rechtsman, FH Stillinger, S Torquato, J. Phys. Chem. A 111, 12816-12821 (2007) 5. Global phase diagram for the honeycomb potential, AP Hynninen, AZ Panagiotopoulos, MC Rechtsman, FH Stillinger, S Torquato, J. Chem. Phys. 125, 024505 (2006)
4. Synthetic diamond and wurtzite structures self-assemble with isotropic pair interactions, MC Rechtsman, FH Stillinger, S Torquato, Phys. Rev. E 75, 031403 (2007) 3. Self-assembly of the simple cubic lattice with an isotropic potential, MC Rechtsman, FH Stillinger, S Torquato, Phys. Rev. E 74, 021404 (2006) 2. Designed interaction potentials via inverse methods for self-assembly, MC Rechtsman, F Stillinger, S Torquato, Phys. Rev. E 73, 011406 (2006) 1. Optimized interactions for targeted self-assembly: application to a honeycomb lattice, MC Rechtsman, FH Stillinger, S Torquato, Phys. Rev. Lett. 95, 228301 (2005) Selected Talks and Seminars PIERS Meeting, Moscow, August 2012 (invited talk) - Direct observation of Anderson localization in optics SIAM Nonlinear Waves Conference, Seattle, June 2012 (invited talk) - Pseudomagneic fields in photonic crystals and lattices (new) CLEO Conference, San Jose, May 2012 (invited talk) - Strain-induced band gap and effective magnetic field in photonic crystals University of Crete, Department of Physics (FORTH) colloquium, Heraklion, Crete - Optical graphene: diffraction-free edge states and strain-induced photonic Landau levels Princeton Center for Theoretical Science, March 2012 (as part of the "Physics of aperiodic systems" series) - Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices Stony Brook University, Department of Physics, March 2012: Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices Yale University, Department of Applied Physics, March 2012: Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices INRS (University of Quebec) invited seminar, Varennes, Quebec, October, 2011: Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices University of Toronto ECTI invited seminar and visiting fellowship, Toronto, Canada, September, 2011: Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices UNC Applied Mathematics Seminar (invited), Chapel Hill, NC, September, 2011: Disorder-enhanced transport in photonic quasicrystals and amorphous photonic lattices Information Photonics 2011, Ottawa, May, 2011 (invited talk): Magnetic field effects and solitons in strained photonic graphene UBC Condensed Matter Physics seminar, Vancouver, May 2011: Disorder-enhanced transport in photonic quasicrystals and topological edge states in optical graphene Conference on Lasers and Electro Optics (CLEO), Baltimore, May, 2011: Magnetic field effects and solitons in strained photonic graphene IMACS Conference on Nonlinear Evolution Equations and Wave Phenomena, Athens, GA, April, 2011: Disorder-enhanced transport in photonic quasicrystals: Anderson localization and delocalization SIAM Conference on Nonlinear Waves and Coherent Structures, Philadelphia, August, 2010: Disorder-enhanced transport in photonic quasicrystals Conference on Lasers and Electro Optics (CLEO), San Jose, May, 2010 (invited talk): Bandgaps in amorphous photonic lattices Dartmouth University Applied Math Seminar, November, 2009: Upper bounds on photonic bandgaps MIT special condensed matter seminar, November, 2009: Upper bounds on photonic bandgaps ETOPIM conference talk, Crete, June 2009: Upper bounds on photonic bandgaps Applied mathematics colloquium, Columbia University, April 2009: Upper bounds on photonic bandgaps Wave propagation seminar, New Jersey Institute of Technology, April 2009, invited talk: Upper bounds on photonic bandgaps Soft matter seminar series, NYU Center for Soft Matter Research, March 2009, invited talk: Upper bounds on photonic bandgaps Grad student / postdoc seminar series, Courant Institute, February 2009, invited talk: Upper bounds on photonic bandgaps Applied math days workshop, Rensselaer Polytechnic Institute, November 2008, invited talk: Optimizing photonic quasicrystals Solid state physics seminar, Brooklyn College, November 2008, invited talk: Optimizing photonic quasicrystals Applied Mathematics Seminar, Courant Institute, September 2008, invited talk: A few inverse problems in statistical mechanics and photonics Princeton Center for Theoretical Science, June 2008, invited talk: Upper bounds on photonic bandgaps “Dynarum" (DARPA collaboration on robust uncertainty management) Kickoff Meeting, January, 2007, Caltech, Pasadena, CA, (invited talk): Inverse Problems and Optimization Techniques for Designed Materials 94th Statistical Mechanics Meeting, December 2005, Rutgers University, Piscataway, NJ: Designed interaction potentials via inverse problems for self-assembly
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