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arXiv · 2307.02952

Density dependent gauge field inducing emergent SSH physics, solitons and condensates in a discrete nonlinear Schr\"odinger equation

William N. Faugno·Mario Salerno·Tomoki Ozawa
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Abstract

We investigate a discrete non-linear Schr\"odinger equation with dynamical, density-difference-dependent, gauge fields. We find a ground-state transition from a plane wave condensate to a localized soliton state as the gauge coupling is varied. Interestingly we find a regime in which the condensate and soliton are both stable. We identify an emergent chiral symmetry, which leads to the existence of a symmetry protected zero energy edge mode. The emergent chiral symmetry relates low and high energy solitons. These states indicate that the interaction acts both repulsively and attractively.

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William N. Faugno, Mario Salerno, Tomoki Ozawa. 2023-07-06. Density dependent gauge field inducing emergent SSH physics, solitons and condensates in a discrete nonlinear Schr\"odinger equation. https://doi.org/10.1103/physrevlett.132.023401

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