Backward Cherenkov radiation emitted by polariton solitons in a microcavity wire

Abstract

Exciton-polaritons in semiconductor microcavities form a highly nonlinear platform to study a variety of effects interfacing optical, condensed matter, quantum and statistical physics. We show that the complex polariton patterns generated by picosecond pulses in microcavity wire waveguides can be understood as the Cherenkov radiation emitted by bright polariton solitons, which is enabled by the unique microcavity polariton dispersion, which has momentum intervals with positive and negative group velocities. Unlike in optical fibres and semiconductor waveguides, we observe that the microcavity wire Cherenkov radiation is predominantly emitted with negative group velocity and therefore propagates backwards relative to the propagation direction of the emitting soliton. We have developed a theory of the microcavity wire polariton solitons and of their Cherenkov radiation and conducted a series of experiments, where we have measured polariton-soliton pulse compression, pulse breaking and emission of the backward Cherenkov radiation.

Transition from Propagating Polariton Solitons to a Standing Wave Condensate Induced by Interactions

“…A large part of the the soliton doublet spectrum now lies below the point of inflection (at k x 1.8 µm −1 ), in the region where polariton effective mass is positive, and where wavepacket defocusing is expected. In this case, solitons can give up their energy to extended dispersive modes with lower k-vectors via Cherenkov radiation [30,33,34]. From a microscopical point of view, this process again can be understood as a result of multiple polariton-polariton scattering events.…”

Dielectric Resonance-Based Optical Metasurfaces: From Fundamentals to Applications

“…Dielectric metasurfaces are compatible with traditional complementary metal-oxide-semiconductor platforms and are promising to achieve on-chip integrated devices. Combined with the development of structured waveguide and microcavity ( Li et al., 2017b ; Skryabin et al., 2017 ), dielectric metasurfaces may integrate different functions together and realize an integrated platform, which can pave the way for future integrated meta-systems supporting mass production in real applications. Hybrid meta-systems on an extreme size.…”

Theory of relaxation oscillations in exciton-polariton condensates

“…which determines whether the fixed point is a stable spiral or a stable node. The analytical condition for relaxation oscillations (25) and the equation for the inactive reservoir stationary density (7) allow for the determination of a diagram in parameter space, presented in Fig. 5, together with typical system dynamics.…”