Quantum phase transition from mixed atommolecule phase to pure molecule phase: Characteristic scaling laws and Berrycurvature signature
Abstract
We investigate the quantum phase transition in an ultracold atommolecule conversion system. It is found that the system undergoes a phase transition from a mixed atommolecule 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:

 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 10502947
 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 atommolecule phase to pure molecule phase: Characteristic scaling laws and Berrycurvature 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 atommolecule phase to pure molecule phase: Characteristic scaling laws and Berrycurvature 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 atommolecule phase to pure molecule phase: Characteristic scaling laws and Berrycurvature signature". United States. doi:10.1103/PHYSREVA.84.023605.
@article{osti_22075503,
title = {Quantum phase transition from mixed atommolecule phase to pure molecule phase: Characteristic scaling laws and Berrycurvature 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 atommolecule conversion system. It is found that the system undergoes a phase transition from a mixed atommolecule 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 = {10502947},
number = 2,
volume = 84,
place = {United States},
year = {2011},
month = {8}
}