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Spin-Orbit Coupled Exciton-Polariton Condensates in Lead Halide Perovskites

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 نشر من قبل Xiaoyang Zhu
 تاريخ النشر 2021
  مجال البحث فيزياء
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Spin-orbit coupling (SOC) is responsible for a range of spintronic and topological processes in condensed matter. Here we show photonic analogs of SOCs in exciton-polaritons and their condensates in microcavities composed of birefringent lead halide perovskite single crystals. The presence of crystalline anisotropy coupled with splitting in the optical cavity of the transverse electric (TE) and transverse magnetic (TM) modes gives rise to a non-Abelian gauge field, which can be described by the Rashba-Dresselhaus Hamiltonian near the degenerate points of the two polarization modes. With increasing density, the exciton polaritons with pseudospin textures undergo phase transitions to competing condensates with orthogonal polarizations. These condensates inherit strong nonlinearity from their excitonic components and may serve as quantum simulators of many-body SOC processes.



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