Protecting coherence in the non-Hermitian two-level system

TL;DR

This paper demonstrates that PT-symmetric non-Hermitian two-level systems can generate, protect, and revive quantum coherence even in dissipative environments, making them promising for quantum information applications.

Contribution

The study constructs a PT-symmetric non-Hermitian two-level system in dissipative environments and shows it can generate and sustain long-lived quantum coherence.

Findings

Quantum coherence can be created from incoherent initial states.

Quantum coherence exhibits long-lived revival in dissipative environments.

Increasing coupling strength {a0} enhances quantum coherence.

Abstract

We have constructed a non-Hermitian two-level system (a PT -symmetric system) in dissipative environments, and investigated the quantum coherence in the non-Hermitian two-level system. Our results show that, quantum coherence can be created by PT -symmetric systems, even if the initial state of the twolevel system is incoherent state. Even though two-level system is interacted with dissipative environments, the quantum coherence exhibits a long-lived revival, and can be protected. We find that the two-level system can obtain more coherence with the coupling strength {\Omega} increases. And we should point out that the PT -symmetric system can be regarded as a good candidate system for creation of the long-lived quantum coherence in dissipative environments.