arXiv:2305.07597 · Physical review. B./Physical review. B

Local geometry and quantum geometric tensor of mixed states

Xu-Yang Hou, Zheng Zhou, Xin Wang, Hao Guo, Chih-Chun Chien

Published Jul 17, 2024• 16 citations

Abstract

The quantum geometric tensor (QGT) encodes information of the local geometry and topology of quantum states. While the QGT of pure quantum states is well known, its generalization to mixed quantum states requires a full characterization of the underlying geometric structure. Here, the authors derive the gauge-invariant QGT of mixed states based on the mathematically rigorous Uhlmann fiber bundle and highlight the similarities and differences of the local geometries of pure and mixed states.

DOI: 10.1103/physrevb.110.035144

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