32 citations · 188 across the 32 of their papers we have counts for
32 papers
Uhlmann Geometry of Fixed-Rank Density Matrices: A Fiber-Bundle Approach
Xu-Yang Hou, Hao Guo
For full-rank density matrices the state space is contractible, the Uhlmann bundle is topologically trivial, and the holonomy admits no quantized invariants; although the Uhlmann p…
Thermal Suppression of Dynamical Quantum Phase Transitions in Finite-Dimensional Systems A Quasi-Hermitian Framework
Jia-Chen Tang, Xu-Yang Hou, Ming-Zhang Wang +1
We investigate dynamical quantum phase transitions (DQPTs) in finite-dimensional systems prepared in thermal equilibrium states and subjected to a sudden quench. A mixed-state Losc…
Wilczek-Zee Realization of Uhlmann Parallel Transport
Yu-Huan Huang, Xu-Yang Hou, Jia-Chen Tang +1
The Uhlmann phase extends geometric phases to mixed quantum states via a parallel-transport condition on purification amplitudes, yet its direct implementation under standard Hamil…
Electrical-Circuit Simulation of the Uhlmann Phase
Yu-Huan Huang, Yu Wang, Jia-Chen Tang +2
The Uhlmann phase extends the concept of geometric phases to mixed quantum states through a parallel-transport condition on purification amplitudes, but its experimental realizatio…
Defect Holonomy Near Rank-Deficient Mixed States
Yu-Huan Huang, Xu-Yang Hou, Hao Guo
We investigate the geometry of mixed quantum states near rank-changing points, showing that these singularities function as effective geometric defects. The Uhlmann connection is w…
Torsion-induced gauge structure in curved quantum waveguides
Xu-Yang Hou, Xianlong Gao, Hao Guo
We investigate the effective dynamics of a particle confined near a space curve. In the strict thin-layer reduction of the nondegenerate transverse ground state, torsion does not e…
Geometry near rank-changing points on the mixed-state manifold: Bures metric, conical singularities, and Lindblad dynamics
Yu-Huan Huang, Xu-Yang Hou, Hao Guo +1
We elucidate the Bures metric in quantum state space near a rank-changing point of the density matrix and show contrasting behavior for two-level () systems versus higher-leve…
Geometric and Topological Obstructions to Hermitianization in Quasi-Hermitian Quantum Systems
Ming-Zhang Wang, Xu-Yang Hou, Hao Guo
Quasi-Hermitian quantum systems, including -symmetric ones, can be mapped to equivalent Hermitian systems via a similarity transformation that redefines the inner pro…
Theory of the Uhlmann Phase in Quasi-Hermitian Quantum Systems
Xu-Yang Hou, Xin Wang, Hao Guo
Geometric phases play a fundamental role in understanding the geometric structure of quantum states, yet extending the Uhlmann phase to non-Hermitian systems poses significant chal…
Evolution of quantum geometric tensor of 1D periodic systems after a quench
Jia-Chen Tang, Xu-Yang Hou, Yu-Huan Huang +1
We investigate the post-quench dynamics of the quantum geometric tensor (QGT) of 1D periodic systems with a suddenly changed Hamiltonian. The diagonal component with respect to the…
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…
Bound-like State in a 1D Self-Similar Delta-Barrier Array
Jia-Chen Tang, Xu-Yang Hou, Yan He +1
We investigate a one-dimensional quantum system with a self-similar arrangement of delta-function potential barriers, exhibiting discrete scale invariance. The singular potential i…
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.…
Mathematical Foundation of the U Quantum Geometric Tensor
Xin Wang, Xu-Yang Hou, Jia-Chen Tang +1
In this paper, we systematically establish the mathematical foundation for the quantum geometric tensor (QGT) of mixed states Explicitly, we present a description b…
Geometry effect of the dynamical quantum phase transitions at finite temperatures
Jia-Chen Tang, Xu-Yang Hou, Hao Guo
Dynamical quantum phase transitions (DQPTs) probe the nonequilibrium evolution of quantum systems, unveiling their geometric and topological characteristics. In this study, we intr…
Machine learning of the Ising model on a spherical Fibonacci lattice
Zheng Zhou, Chen-Hui Song, Xu-Yang Hou +1
We investigate the Ising model on a spherical surface, utilizing a Fibonacci lattice to approximate uniform coverage. This setup poses challenges in achieving consistent lattice di…
Uhlmann quench and geometric dynamic quantum phase transition of mixed states
Jia-Chen Tang, Xu-Yang Hou, Zheng Zhou +2
Dynamic quantum phase transitions (DQPT) following quantum quenches exhibit singular behavior of the overlap between the initial and evolved states. Here we present a formalism to…
Sjqvist quantum geometric tensor of finite-temperature mixed states
Zheng Zhou, Xu-Yang Hou, Xin Wang +3
The quantum geometric tensor (QGT) reveals local geometric properties and associated topological information of quantum states. Here a generalization of the QGT to mixed quantum st…
Interferometric Geometric Phases of -symmetric Quantum Mechanics
Xin Wang, Zheng Zhou, Jia-Chen Tang +3
We present a generalization of the geometric phase to pure and thermal states in -symmetric quantum mechanics (PTQM) based on the approach of the interferometric geom…
Local geometry and quantum geometric tensor of mixed states
Xu-Yang Hou, Zheng Zhou, Xin Wang +2
The quantum geometric tensor (QGT) is a fundamental concept for characterizing the local geometry of quantum states. After casting the geometry of pure quantum states and extractin…
Geometric phases of mixed quantum states: A comparative study of interferometric and Uhlmann phases
Xu-Yang Hou, Xin Wang, Zheng Zhou +2
Two geometric phases of mixed quantum states, known as the interferometric phase and Uhlmann phase, are generalizations of the Berry phase of pure states. After reviewing the two g…
Uhlmann phase of coherent states and the Uhlmann-Berry correspondence
Xin Wang, Xu-Yang Hou, Zheng Zhou +2
We first compare the geometric frameworks behind the Uhlmann and Berry phases in a fiber-bundle language and then evaluate the Uhlmann phases of bosonic and fermionic coherent stat…
Generalizations of Berry phase and differentiation of purified state and thermal vacuum of mixed states
Xu-Yang Hou, Zi-Wen Huang, Zheng Zhou +3
Two representations of mixed states by state-vectors, known as purified state and thermal vacuum, have been realized on quantum computers. While the two representations look simila…
Metamorphic dynamical quantum phase transition in double-quench processes at finite temperatures
Xu-Yang Hou, Qu-Cheng Gao, Hao Guo +1
By deriving a general framework and analyzing concrete examples, we demonstrate a class of dynamical quantum phase transitions (DQPTs) in one-dimensional two-band systems going thr…