Laser Physics Letters

Controllable entropic uncertainty relation in an effective two-level non-Hermitian system

Shi-Qing Tang, Han Liu, Song-Song Li, You-neng Guo

Published Jan 19, 2023• 0 citations

Abstract

Abstract Under the large detuning conditions, a three-level atom in Λ-type configuration reduced to an effective two-level system has been investigated by Shahriar and Hemmer (1990 Phys. Rev. Lett. 65 1865). By introducing unbalanced gain and loss, we in detail investigate the behaviors of entropic uncertainty relation (EUR) in an effective two-level non-Hermitian system. Compared with the dynamics governed by a Hermitian Hamiltonian, we find the EUR in non-Hermitian system is well defined based on the exceptional points of the effective non-Hermitian system, and displays two distinct behaviors. More specifically, when systems possess an exceptional point above which the EUR undergoes an oscillatory behavior, while below which the EUR increases asymptotically to a finite constant value.

DOI: 10.1088/1612-202x/acb1ae

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