3 papers
quant-ph2025
Thermal Uhlmann-Chern Number: Bridging Pure and Mixed States
Xin Wang, Xu-Yang Hou, Yan He +1
Topological properties of quantum systems at finite temperatures, described by mixed states, pose significant challenges due to the triviality of the Uhlmann bundle. We introduce t…
quant-ph2025
Uhlmann and scalar Wilczek-Zee phases of degenerate quantum systems
Xin Wang, Hao Guo, Chih-Chun Chien
The Wilczek-Zee (WZ) holonomy arises in degenerate states while the Uhlmann holonomy characterizes finite-temperature topology. We investigate possible relationships between the Uh…
quant-ph2025
Mixed-state geometric phases of coherent and squeezed spin states
Xin Wang, Jia-Chen Tang, Xu-Yang Hou +2
Two mixed-state geometric phases, known as the Uhlmann phase and interferometric geometric phase (IGP), of spin coherent states (CSSs) and spin squeezed states (SSSs) are analyzed.…