期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：52
页码：14926-14931
DOI：10.1073/pnas.1610123114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceSpin vortices and skyrmions are topological states in exotic phases of matter such as superconductors and superfluids. In these complex states, the spin and orbital angular momentum are both quantized and mixed, resulting in variegated polarization textures. Here we create these composite states in a fluid made of light and matter quasi-particles, polaritons, and demonstrate their reshaping in ultrafast time scales. To describe these dynamics we propose the idea of generalized vortices, a fundamental concept in topology that can be relevant also for applications in the fields of quantum fluids, spintronics, and optical polarization shaping. We study the spin vortices and skyrmions coherently imprinted into an exciton-polariton condensate on a planar semiconductor microcavity. We demonstrate that the presence of a polarization anisotropy can induce a complex dynamics of these structured topologies, leading to the twist of their circuitation on the Poincare sphere of polarizations. The theoretical description of the results carries the concept of generalized quantum vortices in two-component superfluids, which are conformal with polarization loops around an arbitrary axis in the pseudospin space.
