2015/09/30 by M. Iskin · 4 citations
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Gauge theory #Ising model #Optical lattice #Phase transition #Physics #Position and momentum space #Quantum #Quantum many-body systems #Quantum mechanics #Quantum phase transition #Quantum phases #Quasiparticle #Square lattice #Superconductivity #Superfluidity #Topological Materials and Phenomena #Topological order #Topology (electrical circuits) #cond-mat.quant-gas #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physreva.93.013608
published in Physical Review A 93(1) (American Physical Society) · 12 pages with 5 figures
arxiv created 2015/12/17 · openalex publication_date 2016/01/12 · arxiv updated 2016/01/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider a two-component Fermi gas with attractive interactions on a square optical lattice, and study the interplay of Zeeman field, spin-orbit coupling, and next-nearest-neighbor hopping on the ground-state phase diagrams in the entire BCS-BEC evolution. In particular, we first classify and distinguish all possible superfluid phases by the momentum-space topology of their zero-energy quasiparticle-quasihole excitations, and then numerically establish a plethora of quantum phase transitions in between. These transitions are further signaled and evidenced by the changes in the corresponding topological invariant of the system, i.e., its Chern number. Lastly, we find that the superfluid phase exhibits a reentrant structure, separated by a fingering normal phase, the origin of which is traced back to the changes in the single-particle density of states.