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Non-Hermitian fractional quantum Hall states.

ABSTRACT: We demonstrate the emergence of a topological ordered phase for non-Hermitian systems. Specifically, we elucidate that systems with non-Hermitian two-body interactions show a fractional quantum Hall (FQH) state. The non-Hermitian Hamiltonian is considered to be relevant to cold atoms with dissipation. We conclude the emergence of the non-Hermitian FQH state by the presence of the topological degeneracy and by the many-body Chern number for the ground state multiplet showing C_tot?=?1. The robust topological degeneracy against non-Hermiticity arises from the manybody translational symmetry. Furthermore, we discover that the FQH state emerges without any repulsive interactions, which is attributed to a phenomenon reminiscent of the continuous quantum Zeno effect.

SUBMITTER: Yoshida T

PROVIDER: S-EPMC6858315 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Non-Hermitian fractional quantum Hall states.

Yoshida Tsuneya T Kudo Koji K Hatsugai Yasuhiro Y

Scientific reports 20191115 1

We demonstrate the emergence of a topological ordered phase for non-Hermitian systems. Specifically, we elucidate that systems with non-Hermitian two-body interactions show a fractional quantum Hall (FQH) state. The non-Hermitian Hamiltonian is considered to be relevant to cold atoms with dissipation. We conclude the emergence of the non-Hermitian FQH state by the presence of the topological degeneracy and by the many-body Chern number for the ground state multiplet showing C<sub>tot</sub> = 1. ...[more]

PMID: 31729412

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