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arXiv · 2201.01891

Chiral edge soliton in nonlinear Chern systems

Motohiko Ezawa
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Abstract

We study the effect on the chiral edge states by including a nonlinearity to a Chern insulator which has two chiral edge states with opposite chiralities. We explore a quench dynamics by giving a pulse to one site on an edge and analyzing the time evolution of a wave packet. Without the nonlinearity, an initial pulse spreads symmetrically and diffuses. On the other hand, with the nonlinearity present, a solitary wave is formed by the self-trapping effect of the nonlinear term and undergoes a unidirectional propagation along the edge, which we identify as a chiral edge soliton. A further increase of the nonlinearity induces a self-trapping transition, where the chiral wave packet stops its motion. It is intriguing that the nonlinearity is controlled only by changing the initial condition without changing a sample.

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Motohiko Ezawa. 2022-01-06. Chiral edge soliton in nonlinear Chern systems. https://doi.org/10.1103/physrevb.106.195423

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