E. S. Sedov

Hyperbolic Metamaterials with Bragg Polaritons.

We propose a novel mechanism for designing quantum hyperbolic metamaterials with the use of semiconductor Bragg mirrors containing periodically arranged quantum wells. The hyperbolic dispersion of exciton-polariton modes is realized near the top of the first allowed photonic miniband in such a structure which leads to the formation of exciton-polariton X waves. Exciton-light coupling provides a resonant nonlinearity which leads to nontrivial topologic solutions. We predict the formation of low amplitude spatially localized oscillatory structures: oscillons described by kink shaped solutions of the effective Ginzburg-Landau-Higgs equation. The oscillons have direct analogies in gravitational theory. We discuss implementation of exciton-polariton Higgs fields for the Schrödinger cat state generation.

Solitons in cavity-QED arrays containing interacting qubits

(Dated: August 1, 2012)We reveal the existence of polariton soliton solutions in the array of weakly coupled optical cavities,each containing an ensemble of interacting qubits. An effective complex Ginzburg-Landau equationis derived in the continuum limit taking into account the effects of cavity field dissipation and qubitdephasing. We have shown that an enhancement of the induced nonlinearity can be achieved by twoorder of the magnitude with a negative interaction strength which implies a large negative qubit-fielddetuning as well. Bright solitons are found to be supported under perturbations only in the upper(optical) branch of polaritons, for which the corresponding group velocity is controlled by tuningthe interacting strength. With the help of perturbation theory for solitons, we also demonstratethat the group velocity of these polariton solitons is suppressed by the diffusion process.I. INTRODUCTION

Light propagation in tunable exciton-polariton one-dimensional photonic crystals

Simulations of propagation of light beams in specially designed multilayer semiconductor structures (one-dimensional photonic crystals) with embedded quantum wells reveal characteristic optical properties of resonant hyperbolic metamaterials. A strong dependence of the refraction angle and the optical beam spread on the exciton radiative lifetime is revealed. We demonstrate the strong negative refraction of light and the control of the group velocity of light by an external bias through its effect upon the exciton radiative properties.

Tunneling-assisted optical information storage with lattice polariton solitons in cavity-QED arrays

Considering two-level media in the array of weakly coupled nano-cavities, we reveal a variety of dynamical regimes, such as diffusion, self-trapping, soliton, and breathers for the wave-packets in the presence of photon tunneling processes between the next-nearest cavities. We focus our attention on the low branch (LB) bright polariton soliton formation, due to the two-body polariton-polariton scattering processes. When detuning frequency is manipulated adiabatically, the low-branch lattice polariton localized states, i.e., that are solitons and breathers evolving between photon-like and matter-like states, are shown to act as carriers for spatially distributed storage and retrieval of optical information.

Artificial gravity effect on spin-polarized exciton-polaritons

The pseudospin dynamics of long-living exciton-polaritons in a wedged 2D cavity has been studied theoretically accounting for the external magnetic field effect. The cavity width variation plays the role of the artificial gravitational force acting on a massive particle: exciton-polariton. A semi-classical model of the spin-polarization dynamics of ballistically propagating exciton-polaritons has been developed. It has been shown that for the specific choice of the magnetic field magnitude and the initial polariton wave vector the polariton polarization vector tends to an attractor on the Poincaré sphere. Based on this effect, the switching of the polariton polarization in the ballistic regime has been demonstrated. The self-interference of the polariton field emitted by a point-like source has been shown to induce the formation of interference patterns.

Oscillations of the Degree of Circular Polarization in the Optical Spin Hall Effect

The optical spin Hall effect appears when elastically scattered exciton polaritons couple to an effective magnetic field inside of quantum wells in semiconductor microcavities. Theory predicts an oscillation of the pseudospin of the exciton polaritons in time. Here, we present a detailed analysis of momentum space dynamics of the exciton polariton pseudospin. Compared to what is predicted by theory, we find a higher modulation of the temporal oscillations of the pseudospin. We attribute the higher modulation to additional components of the effective magnetic field which have been neglected in the foundational theory of the optical spin Hall effect. Adjusting the model by adding non-linear polariton-polariton interactions, we find a good agreement in between the experimental results and simulations.

Control of propagation of spatially localized polariton wave packets in a Bragg mirror with embedded quantum wells

We considered the nonlinear dynamics of Bragg polaritons in a specially designed stratified semiconductor structure with embedded quantum wells, which possesses a convex dispersion. The model for the ensemble of single periodically arranged quantum wells coupled with the Bragg photon fields has been developed. In particular, the generalized Gross-Pitaevskii equation with the non-parabolic dispersion has been obtained for the Bragg polariton wave function. We revealed a number of dynamical regimes for polariton wave packets resulting from competition of the convex dispersion and the repulsive nonlinearity effects. Among the regimes are spreading, breathing and soliton propagation. When the control parameters including the exciton-photon detuning, the matter-field coupling and the nonlinearity are manipulated, the dynamical regimes switch between themselves.

Dynamics of the optical spin Hall effect

We gratefully acknowledge the financial support by the Deutsche Forschungsgemeinschaft in the frame of the ICRC TRR 160 within project B7. The Wurzburg group acknowledges the support by the Deutsche Forschungsgemeinschaft within the project SCHN1376-3.1. E.S. acknowledges support from the Russian Foundation for Basic Research grant No. 16-32-60104. A.K. and E.S. acknowledge support from the EPSRC Hybrid Polaritonics Programme grant. A.K. acknowledges the partial support from the HORIZON 2020 RISE project CoExAn (Grant No. 644076).

Atomic Bose-Einstein condensates as nonlinear hyperbolic metamaterials

We consider the problem of formation of small amplitude spatially localized oscillatory structures for atomic Bose-Einstein condensate (BEC) confined in two and three dimensional optical lattices (OLs), respectively. By using kp-method we have demonstrated mapping of the initial Gross-Pitaevskii equation on nonlinear Klein-Gordon equations. Formation of breather-like oscillating localized states - atomic oscillons - have been predicted in this case.

Quantum hyperbolic metamaterials with exciton-polaritons in semiconductor Bragg mirrors

A novel mechanism for realization of hyperbolic metamaterials with use of spatially periodic semiconductor Bragg mirrors containing periodically arranged quantum wells is proposed. The hyperbolic dispersion of exciton-polariton modes is realized near the top of the first allowed photonic mini-band in the structure. We predict formation of low amplitude breather-like oscillatory structures: oscillons described by kink shaped solutions of the effective Ginzburg-Landau-Higgs equation.