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تسجيل مستخدم جديدSpiraling vortices in exciton-polariton condensates
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We introduce the phenomenon of spiraling vortices in driven-dissipative (non-equilibrium) exciton-polariton condensates excited by a non-resonant pump beam. At suitable low pump intensities, these vortices are shown to spiral along circular trajectories whose diameter is inversely proportional to the effective mass of the polaritons, while the rotation period is mass independent. Both diameter and rotation period are inversely proportional to the pump intensity. Stable spiraling patterns in the form of complexes of multiple mutually-interacting vortices are also found. At elevated pump intensities, which create a stronger homogeneous background, we observe more complex vortex trajectories resembling Spirograph patterns.
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Recently a new type of system exhibiting spontaneous coherence has emerged -- the exciton-polariton condensate. Exciton-polaritons (or polaritons for short) are bosonic quasiparticles that exist inside semiconductor microcavities, consisting of a sup
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