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arXiv · 2308.07853

Manipulation of Weyl Points in Reciprocal and Nonreciprocal Mechanical Lattices

Mingsheng Tian·Ivan Velkovsky·Tao Chen·Fengxiao Sun·Qiongyi He·Bryce Gadway
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Abstract

We introduce feedback-measurement technologies to achieve flexible control of Weyl points and conduct the first experimental demonstration of Weyl type I-II transition in mechanical systems. We demonstrate that non-Hermiticity can expand the Fermi arc surface states from connecting Weyl points to Weyl rings, and lead to a localization transition of edge states influenced by the interplay between band topology and the non-Hermitian skin effect. Our findings offer valuable insights into the design and manipulation of Weyl points in mechanical systems, providing a promising avenue for manipulating topological modes in non-Hermitian systems.

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Mingsheng Tian, Ivan Velkovsky, Tao Chen, Fengxiao Sun, Qiongyi He, Bryce Gadway. 2023-08-15. Manipulation of Weyl Points in Reciprocal and Nonreciprocal Mechanical Lattices. https://doi.org/10.1103/physrevlett.132.126602

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