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arXiv · 2211.06043

Topologically bound states, non-Hermitian skin effect and flat bands, induced by two-particle interaction

Alexander N. Poddubny
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Abstract

We study theoretically quantum states of two repelling spinless particles in a one-dimensional tight-binding model with simple periodic lattice and open boundary conditions. We demonstrate, that when the particles are not identical, their interaction drives nontrivial correlated two-particle states, such as bound states, edge states as well as interaction-induced flat bands. Specifically, the center-of-mass and relative motions of two particles become coupled in a topologically nontrivial way. By virtue of the non-Hermitian skin effect the localization of the center of mass enforces the localization of the relative motion and formation of the bound states.

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Alexander N. Poddubny. 2022-11-11. Topologically bound states, non-Hermitian skin effect and flat bands, induced by two-particle interaction. https://arxiv.org/abs/2211.06043

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