2008/01/09 by Zhe Chang, Ping Wang, Chang, Zhe +1
Physics and Astronomy · #FOS: Physical sciences #Quantum Physics (quant-ph) #Quantum many-body systems #quant-ph
paper · pdf · doi:10.48550/arxiv.0801.1400
5 pages
arxiv created 2008/01/09 · openalex publication_date 2008/01/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The standard Landau-Ginzburg scenario of phase transition is broken down for quantum phase transition. It is difficult to find an order parameter to indicate different phases for quantum fluctuations. Here, we suggest a topological description of the quantum phase transition for the XY model. The ground states are identified as a specialized U(1) principal bundle on the base manifold S2. And then different first Chern numbers of U(1) principal bundle on the base manifold S2 are associated to each phase of quantum fluctuations. The particle-hole picture is used to parameterized the ground states of the XY system. We show that a singularity of the Chern number of the ground states occurs simultaneously with a quantum phase transition. The Chern number is a suitable topological order of the quantum phase transition.