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arXiv · 1609.02665

The effects of dissipation on topological mechanical systems

Ye Xiong·Tianxiang Wang·Peiqing Tong
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Abstract

We theoretically study the effects of isotropic dissipation in a topological mechanical system which is an analogue of Chern insulator in mechanical vibrational lattice. The global gauge invariance is still conserved in this system albeit it is destroyed by the dissipation in the quantum counterpart. The chiral edge states in this system are therefore robust against strong dissipation. The dissipation also causes a dispersion of damping for the eigenstates. It will modify the equation of motion of a wave packet by an extra effective force. After taking into account the Berry curvature in the wave vector space, the trace of a free wave packet in the real space should be curved, feinting to break the Newton's first law.

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Ye Xiong, Tianxiang Wang, Peiqing Tong. 2016-09-09. The effects of dissipation on topological mechanical systems. https://doi.org/10.1038/srep32572

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