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arXiv · 2211.04233

Topological extension including quantum jump

Xiangyu Niu·Junjie Wang
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Abstract

Non-Hermitian systems and the Lindblad form master equation have always been regarded as reliable tools in dissipative modeling. Intriguingly, existing literature often obtains an equivalent non-Hermitian Hamiltonian by neglecting the quantum jumping terms in the master equation. However, there lacks investigation into the effects of discarded terms as well as the unified connection between these two approaches. In this study, we study the Su-Schrieffer-Heeger model with collective loss and gain from a topological perspective. When the system undergoes no quantum jump events, the corresponding shape matrix exhibits the same topological properties in contrast to the traditional non-Hermitian theory. Conversely, the occurrence of quantum jumps can result in a shift in the positions of the phase transition. Our study provides a qualitative analysis of the impact of quantum jumping terms and reveals their unique role in quantum systems.

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Xiangyu Niu, Junjie Wang. 2022-11-08. Topological extension including quantum jump. https://doi.org/10.1088/1751-8121/ad330c

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