Topological quantum phase transition in the BEC-BCS crossover phenomena
arXiv:1003.4735 · doi:10.1103/PhysRevB.82.073105
Abstract
A crossover between the Bose Einstein condensation (BEC) and BCS superconducting state is described topologically in the chiral symmetric fermion system with attractive interaction. Using a local Z_2 Berry phase, we found a quantum phase transition between the BEC and BCS phases without accompanying the bulk gap closing.
4 pages, 5 figures
References in corpus (8)
- Quantum Spin Hall Insulator State in HgTe Quantum Wells
- Crossover from a molecular Bose-Einstein condensate to a degenerate Fermi gas
- Topological Classification of Gapped Spin Chains :Quantized Berry Phase as a Local Order Parameter
- Exact Analysis of Entanglement in Gapped Quantum Spin Chains
- Degeneracy and Consistency Condition of Berry phases: Gap Closing under the Twist
- Topological Identification of Spin-1/2 Two-Leg Ladder with Four-Spin Ring Exchange
- Edge states in graphene in magnetic fields -- a speciality of the edge mode embedded in the n=0 Landau band
- Edge states of Spin-1/2 Two-Leg Ladder with Four-Spin Ring Exchange