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arXiv · 1611.02239

Weyl Exceptional Rings in a Three-Dimensional Dissipative Cold Atomic Gas

Yong Xu·Sheng-Tao Wang·L. -M. Duan
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Abstract

Three-dimensional topological Weyl semimetals can generally support a zero-dimensional Weyl point characterized by a quantized Chern number or a one-dimensional Weyl nodal ring (or line) characterized by a quantized Berry phase in the momentum space. Here, in a dissipative system with particle gain and loss, we discover a new type of topological ring, dubbed Weyl exceptional ring consisting of exceptional points at which two eigenstates coalesce. Such a Weyl exceptional ring is characterized by both a quantized Chern number and a quantized Berry phase, which are defined via the Riemann surface. We propose an experimental scheme to realize and measure the Weyl exceptional ring in a dissipative cold atomic gas trapped in an optical lattice.

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Yong Xu, Sheng-Tao Wang, L. -M. Duan. 2016-11-14. Weyl Exceptional Rings in a Three-Dimensional Dissipative Cold Atomic Gas. https://doi.org/10.1103/physrevlett.118.045701

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