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Title: Quantum phase transition from mixed atom-molecule phase to pure molecule phase: Characteristic scaling laws and Berry-curvature signature

Abstract

We investigate the quantum phase transition in an ultracold atom-molecule conversion system. It is found that the system undergoes a phase transition from a mixed atom-molecule phase to a pure molecule phase when the energy bias exceeds a critical value. By constructing a coherent state as variational state, we get a good approximation of the quantum ground state of the system. Using this variational state, we deduce the critical point analytically. We then discuss the scaling laws characterizing the transition and obtain the corresponding critical exponents. Furthermore, the Berry curvature signature of the transition is studied. In particular, we find that the derivatives of the Berry curvature with respect to total particle number intersect at the critical point. The underlying mechanism of this finding is discussed as well.

Authors:
 [1];  [1]
  1. Science and Technology Computation Physics Laboratory, Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)
Publication Date:
OSTI Identifier:
22075503
Resource Type:
Journal Article
Journal Name:
Physical Review. A
Additional Journal Information:
Journal Volume: 84; Journal Issue: 2; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1050-2947
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; ATOMS; EIGENSTATES; GROUND STATES; MOLECULES; PHASE TRANSFORMATIONS; SCALING LAWS; VARIATIONAL METHODS

Citation Formats

Shengchang, Li, Graduate School, China Academy of Engineering Physics, Beijing 100088, Libin, Fu, and Center for Applied Physics and Technology, Peking University, Beijing 100084. Quantum phase transition from mixed atom-molecule phase to pure molecule phase: Characteristic scaling laws and Berry-curvature signature. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.84.023605.
Shengchang, Li, Graduate School, China Academy of Engineering Physics, Beijing 100088, Libin, Fu, & Center for Applied Physics and Technology, Peking University, Beijing 100084. Quantum phase transition from mixed atom-molecule phase to pure molecule phase: Characteristic scaling laws and Berry-curvature signature. United States. doi:10.1103/PHYSREVA.84.023605.
Shengchang, Li, Graduate School, China Academy of Engineering Physics, Beijing 100088, Libin, Fu, and Center for Applied Physics and Technology, Peking University, Beijing 100084. Mon . "Quantum phase transition from mixed atom-molecule phase to pure molecule phase: Characteristic scaling laws and Berry-curvature signature". United States. doi:10.1103/PHYSREVA.84.023605.
@article{osti_22075503,
title = {Quantum phase transition from mixed atom-molecule phase to pure molecule phase: Characteristic scaling laws and Berry-curvature signature},
author = {Shengchang, Li and Graduate School, China Academy of Engineering Physics, Beijing 100088 and Libin, Fu and Center for Applied Physics and Technology, Peking University, Beijing 100084},
abstractNote = {We investigate the quantum phase transition in an ultracold atom-molecule conversion system. It is found that the system undergoes a phase transition from a mixed atom-molecule phase to a pure molecule phase when the energy bias exceeds a critical value. By constructing a coherent state as variational state, we get a good approximation of the quantum ground state of the system. Using this variational state, we deduce the critical point analytically. We then discuss the scaling laws characterizing the transition and obtain the corresponding critical exponents. Furthermore, the Berry curvature signature of the transition is studied. In particular, we find that the derivatives of the Berry curvature with respect to total particle number intersect at the critical point. The underlying mechanism of this finding is discussed as well.},
doi = {10.1103/PHYSREVA.84.023605},
journal = {Physical Review. A},
issn = {1050-2947},
number = 2,
volume = 84,
place = {United States},
year = {2011},
month = {8}
}