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arXiv · 1910.03503

Ideal type-II Weyl points in topological circuits

Rujiang Li·Bo Lv·Huibin Tao·Jinhui Shi·Yidong Chong·Baile Zhang·Hongsheng Chen
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Abstract

Weyl points (WPs), as nodal degenerate points in three-dimensional (3D) momentum space, are ideal if they are symmetry-related, well-separated, residing at the same energy and far from the nontopological bands. Although type-II WPs show some unique features compared with type-I counterparts, ideal type-II WPs have not yet been reported due to the lack of an ideal Weyl system with enough flexibility to tilt the dispersion bands. By stacking two-dimensional (2D) layers of inductor-capacitor (LC) resonator dimers with the breaking of parity inversion symmetry, here we experimentally realize the topological circuits with only the topological bands and observe a minimal number of four ideal type-II WPs. Two hallmark features of type-II WPs: a strongly tilted band structure with two group velocities having the same sign near type-II WPs and the topological surface states in an incomplete bandgap have been demonstrated. Our results establish an ideal system to the further study of Weyl physics and provide a new perspective to the access of topological matters.

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Rujiang Li, Bo Lv, Huibin Tao, Jinhui Shi, Yidong Chong, Baile Zhang, Hongsheng Chen. 2019-10-07. Ideal type-II Weyl points in topological circuits. https://doi.org/10.1093/nsr%2Fnwaa192

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