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A. V. Kavokin - One of the best experts on this subject based on the ideXlab platform.
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Spin noise in polariton lasers
arXiv: Mesoscale and Nanoscale Physics, 2013Co-Authors: Mikhail M. Glazov, M. A. Semina, E. Ya. Sherman, A. V. KavokinAbstract:We develop a theory of spin fluctuations of exciton-Polaritons in a quantum microcavity under the non-resonant unpolarized pumping. It is shown that the spin noise is sensitive to the scattering rates in the system, occupation of the ground state, statistics of Polaritons and interactions. The spin noise spectrum drastically narrows in the polariton lasing regime due to formation of a polariton condensate, while its shape becomes non-Lorentzian owing to interaction-induced spin decoherence.
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Spin Effects in Exciton–Polariton Condensates
Exciton Polaritons in Microcavities, 2012Co-Authors: A. V. KavokinAbstract:Exciton–Polaritons in microcavities form an unusual gas of weakly interacting bosons. It has no direct analogy in cold atomic gases, superfluids or superconductors due to its two-component spin structure: in typical planar microcavities the Polaritons have two allowed spin projections to the structure axis. This is why the order parameter of a polariton condensate is a complex spinor. The magnitude and, possibly, sign of polariton–polariton interaction constant depends on the spin state of Polaritons. The energy of an exciton–polariton condensate is also spin-dependent. These specific features make polariton condensates a unique laboratory for studies of spin effects in interacting Bose gases. Several new spin-dependent effects in polariton condensates have been theoretically predicted and experimentally observed during the recent decade. This review chapter addresses some of these effects: polarisation multistability, spin switching, spin rings and spin Meissner effect. In the last section we address the perspective of observation of spin superfluidity in microcavities.
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Spin-dependent polariton-polariton scattering in planar microcavities
Superlattices and Microstructures, 2010Co-Authors: L. Pilozzi, M.m. Glazov, Henni Ouerdane, Guillaume Malpuech, A. V. Kavokin, A. D'andreaAbstract:We present a microscopic theory of polariton-polariton (PP) scattering in quantum microcavities, which is developed with allowance for the composite nature of Polaritons. Analytical estimations of the effective scattering rate for PP scattering with parallel spin configuration are presented, and the role of dark excitons in the opposite spin configuration is discussed.
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Spin-dependent polariton–polariton scattering in planar microcavities
Superlattices and Microstructures, 2010Co-Authors: L. Pilozzi, M.m. Glazov, Henni Ouerdane, Guillaume Malpuech, A. V. Kavokin, A. D'andreaAbstract:Abstract We present a microscopic theory of polariton–polariton (PP) scattering in quantum microcavities, which is developed with allowance for the composite nature of Polaritons. Analytical estimations of the effective scattering rate for PP scattering with parallel spin configuration are presented, and the role of dark excitons in the opposite spin configuration is discussed.
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Interference of coherent polariton beams in microcavities: polarization controlled optical gates
Physical Review Letters, 2007Co-Authors: Charles Leyder, A. V. Kavokin, Tim C.h. Liew, Ivan A. Shelykh, Marco Romanelli, Jean-philippe Karr, Elisabeth Giacobino, Alberto BramatiAbstract:We demonstrate, theoretically and experimentally, a polarization-controlled optical gate based on a degenerate polariton-polariton scattering process occurring in semiconductor microcavities. Because of the interference between coherent Polaritons, this process is observed in the case of Polaritons generated from two collinearly polarized coherent pump beams. On the contrary, if the beams are cross polarized, the scattering is suppressed.
Guillaume Malpuech - One of the best experts on this subject based on the ideXlab platform.
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Microcavity Polaritons for topological photonics
2020Co-Authors: Dmitry D. Solnyshkov, Jacqueline Bloch, Guillaume Malpuech, Philippe St-jean, Sylvain Ravets, Alberto AmoAbstract:Microcavity Polaritons are light-matter quasiparticles that arise from the strong coupling between excitons and photons confined in a semiconductor microcavity. They typically operate at visible or near visible wavelengths. They combine the properties of confined electromagnetic fields, including a sizeable spin-orbit coupling, and the sensitivity to external magnetic fields and particle interactions inherited from their partly matter nature. These features make Polaritons an excellent platform to study topological phases in photonics in one and two dimensional lattices, which band properties can be directly accessed using standard optical tools. In this review we describe the main properties of microcavity Polaritons and the main observations in the field of topological photonics, which include, among others, lasing in topological edge states, the implementation of a polariton Chern insulator under an external magnetic field and the direct measurement of fundamental quantities such as the quantum geometric tensor and winding numbers in one- and two-dimensional lattices. Polariton interactions open exciting perspectives for the study of nonlinear topological phases.
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Spin-dependent polariton-polariton scattering in planar microcavities
Superlattices and Microstructures, 2010Co-Authors: L. Pilozzi, M.m. Glazov, Henni Ouerdane, Guillaume Malpuech, A. V. Kavokin, A. D'andreaAbstract:We present a microscopic theory of polariton-polariton (PP) scattering in quantum microcavities, which is developed with allowance for the composite nature of Polaritons. Analytical estimations of the effective scattering rate for PP scattering with parallel spin configuration are presented, and the role of dark excitons in the opposite spin configuration is discussed.
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Spin-dependent polariton–polariton scattering in planar microcavities
Superlattices and Microstructures, 2010Co-Authors: L. Pilozzi, M.m. Glazov, Henni Ouerdane, Guillaume Malpuech, A. V. Kavokin, A. D'andreaAbstract:Abstract We present a microscopic theory of polariton–polariton (PP) scattering in quantum microcavities, which is developed with allowance for the composite nature of Polaritons. Analytical estimations of the effective scattering rate for PP scattering with parallel spin configuration are presented, and the role of dark excitons in the opposite spin configuration is discussed.
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Anisotropic polariton scattering and spin dynamics of cavity Polaritons
Solid State Communications, 2005Co-Authors: M.m. Glazov, Guillaume Malpuech, A. V. Kavokin, I.a. Shelykh, K.v. Kavokin, D.d. SolnyshkovAbstract:We describe the spin-dynamics of exciton–Polaritons in semiconductor microcavities in the strong coupling regime. Using the Liouville equation for the spin-density matrix in the Born–Markov approximation we obtain kinetic equations taking into account polariton–acoustic phonon and polariton–polariton scattering. We describe both the ‘polariton laser’ regime (non-resonant excitation) and ‘optical parametric oscillator’ regime (resonant excitation at the magic angle). We obtain a good agreement with experimental data on the dynamics of polarization of light emitted by microcavities
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Order parameter dynamics of a Bose-Einstein condensate of exciton-Polaritons in semiconductor microcavities
2005Co-Authors: I. Shelykh, A. V. Kavokin, F. P. Laussy, Guillaume MalpuechAbstract:It is shown theoretically that Bose condensation of spin-degenerated exciton-Polaritons results in spontaneous buildup of the linear polarization in emission spectra of semiconductor microcavities. The linear polarization degree is a good order parameter for the polariton Bose condensation. If spin-degeneracy is lifted, an elliptically polarized light is emitted by the polariton condensate. The main axis of the ellipse rotates in time due to self-induced Larmor precession of the polariton condensate pseudospin. The polarization decay time is governed by the dephasing induced by the polariton-polariton interaction and strongly depends on the statistics of the condensed state.
Alberto Bramati - One of the best experts on this subject based on the ideXlab platform.
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Interference of coherent polariton beams in microcavities: polarization controlled optical gates
Physical Review Letters, 2007Co-Authors: Charles Leyder, A. V. Kavokin, Tim C.h. Liew, Ivan A. Shelykh, Marco Romanelli, Jean-philippe Karr, Elisabeth Giacobino, Alberto BramatiAbstract:We demonstrate, theoretically and experimentally, a polarization-controlled optical gate based on a degenerate polariton-polariton scattering process occurring in semiconductor microcavities. Because of the interference between coherent Polaritons, this process is observed in the case of Polaritons generated from two collinearly polarized coherent pump beams. On the contrary, if the beams are cross polarized, the scattering is suppressed.
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Quantum degeneracy of microcavity Polaritons
Physical Review Letters, 2006Co-Authors: Augustin Baas, Marco Romanelli, Jean-philippe Karr, Alberto Bramati, Elisabeth GiacobinoAbstract:We investigate experimentally one of the main features of a quantum fluid constituted by exciton Polaritons in a semiconductor microcavity , that is quantum degeneracy of a macroscopic fraction of the particles. We show that resonant pumping allows to create a macroscopic population of Polaritons in one quantum state. Furthermore we demonstrate that parametric polariton scattering results in the transfer of a macroscopic population of polariton from one single quantum state into another one. Finally we briefly outline a simple method which provides direct evidence of the first-order spatial coherence of the transferred population.
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Towards quantum correlated polariton modes in semiconductor microcavities
Journal of Optics B, 2005Co-Authors: Marco Romanelli, Charles Leyder, Jean-philippe Karr, Elisabeth Giacobino, Augustin Baas, Alberto BramatiAbstract:In planar semiconductor microcavities in the strong coupling regime, nonlinear effects such as Kerr-like effect, parametric fluorescence and parametric oscillation are observed, as a result of parametric scattering of Polaritons. After discussing the basic physical properties of the system and their theoretical description, we report on our experimental demonstration of polariton squeezing in the degenerate scattering configuration (Kerr configuration), and on the generation of correlated Polaritons in the nondegenerate configuration. The latter results open the way to the generation of quantum correlated polariton modes.
Stefan Linden - One of the best experts on this subject based on the ideXlab platform.
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Transverse Anderson localization of surface plasmon Polaritons
Optics letters, 2017Co-Authors: Zlata Cherpakova, Felix Bleckmann, T. Vogler, Stefan LindenAbstract:We investigate the effect of disorder on the propagation of surface plasmon Polaritons in arrays of evanescently coupled dielectric loaded surface plasmon polariton waveguides. Diagonal disorder is implemented by randomly varying the heights of the waveguides. Real-space as well as momentum-space images of the surface plasmon polariton intensity distribution in the waveguide arrays are recorded by leakage radiation microscopy. In real space, increasing disorder results in a transverse localization of surface plasmon Polaritons. In the momentum distribution, we observe for the first time a disorder-induced transition from a continuous band to a set of discrete modes.
Zhigao Dai - One of the best experts on this subject based on the ideXlab platform.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Saul Velez, Christopher Tollan, Zhigao DaiAbstract:Polaritons-hybrid light-matter excitations-enable nanoscale control of light. Particularly large polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic polariton propagation in natural materials has so far remained elusive. Here we report anisotropic polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3-5. From signal oscillations in real-space images we measure polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light-matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics.
