4 research outputs found
Backward Cherenkov radiation emitted by polariton solitons in a microcavity wire
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
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Spatial patterns of dissipative polariton solitons in semiconductor microcavities
We report propagating bound microcavity polariton soliton arrays consisting of multipeak structures
either along (x) or perpendicular (y) to the direction of propagation. Soliton arrays of up to five solitons are
observed, with the number of solitons controlled by the size and power of the triggering laser pulse. The
breakup along the x direction occurs when the effective area of the trigger pulse exceeds the characteristic
soliton size determined by polariton-polariton interactions. Narrowing of soliton emission in energymomentum
space indicates phase locking between adjacent solitons, consistent with numerical modeling
which predicts stable multihump soliton solutions. In the y direction, the breakup originates from
inhomogeneity across the wave front in the transverse direction which develops into a stable array only in
the solitonic regime via phase-dependent interactions of propagating fronts