2017/02/28 by Ying-Hai Wu, Xiaopeng Li, S. Das Sarma
Physics and Astronomy · #Bose–Einstein condensate #Boson #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Optical lattice #Physics #Quantum #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Quantum, superfluid, helium dynamics #Spin (aerodynamics) #Spinor #Spintronics #Superfluidity #cond-mat.quant-gas #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.96.214502
published as Phys. Rev. B 96, 214502 (2017) · 5 pages, 4 figures
openalex publication_date 2017/12/07 · arxiv created 2017/12/14 · arxiv updated 2017/12/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study a spinor (two-component) Bose gas confined in a one-dimensional double-valley optical lattice which has a double-well structure in momentum space. Based on field theory analysis, it is found that spinor bosons in the double-valley band may form a spin-charge mixed chiral spin quasicondensate under certain conditions. Our numerical calculations in a concrete \ensuremathπ-flux triangular ladder system confirm the robustness of the chiral spin order against interactions and quantum fluctuations. This exotic atomic Bose-Einstein condensate exhibits spatially staggered spin loop currents without any charge dynamics despite the complete absence of spin-orbit coupling in the system, creating an interesting approach to atom spintronics. The entanglement entropy scaling allows us to extract conformal-field-theory central charge and establish the low-energy effective field theory for the chiral spin condensate as a two-component Luttinger liquid. Our predictions should be detectable in atomic experiments through spin-resolved time-of-flight techniques.