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Topological gapless matters in three-dimensional ultracold atomic gases

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Abstract

Three-dimensional topological gapless matters with gapless degeneracies protected by a topological invariant defined over a closed manifold in momentum space have attracted considerable interest in various fields ranging from condensed matter materials to ultracold atomic gases. As a highly controllable and disorder free system, ultracold atomic gases provide a versatile platform to simulate topological gapless matters. Here, the current progress in studies of topological gapless phenomena in three-dimensional cold atom systems is summarized in the review. It is mainly focused on Weyl points, structured (type-II) Weyl points, Dirac points, nodal rings and Weyl exceptional rings in cold atoms. Since interactions in cold atoms can be controlled via Feshbach resonances, the progress in both superfluids for attractive interactions and non-interacting cold atom gases is reviewed.

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Authors and Affiliations

  1. Center for Quantum Information, IIIS, Tsinghua University, Beijing, 100084, China

    Yong Xu

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  1. Yong Xu
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Correspondence to Yong Xu.

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Acknowledgements

We appreciate the collaboration with C. Zhang, L.-M. Duan, F. Zhang, S.-T. Wang, R.-L. Chu, Y. Hu and Y.-B. Yang. We thank Q.-B. Zeng, Y.-B. Yang and Y.-L. Tao for helpful discussions and critical reading of the manuscript. This work was supported by the start-up program of Tsinghua University and the National Thousand-Young-Talents Program.

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Xu, Y. Topological gapless matters in three-dimensional ultracold atomic gases. Front. Phys. 14, 43402 (2019). https://doi.org/10.1007/s11467-019-0896-1

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  • DOI: https://doi.org/10.1007/s11467-019-0896-1

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