998 research outputs found
Many-body ground state localization and coexistence of localized and extended states in an interacting quasiperiodic system
We study the localization problem of one-dimensional interacting spinless
fermions in an incommensurate optical lattice, which changes from an extended
phase to a nonergoic many-body localized phase by increasing the strength of
the incommensurate potential. We identify that there exists an intermediate
regime before the system enters the many-body localized phase, in which both
the localized and extended many-body states coexist, thus the system is divided
into three different phases, which can be characterized by normalized
participation ratios of the many-body eigenstates and distributions of natural
orbitals of the corresponding one-particle density matrix. This is very
different from its noninterating limit, in which all eigenstaes undergo a
delocaliztion-localization transtion when the strength of the incommensurate
potential exceeds a critical value.Comment: 5 pages, 6 figure
Ferromagnetic to antiferromagnetic transition of one-dimensional spinor Bose gases with spin-orbit coupling
We have analytically solved one-dimensional interacting two-component bosonic
gases with spin-orbit (SO) coupling by the Bethe-ansatz method. Through a gauge
transformation, the effect of SO coupling is incorporated into a spin-dependent
twisted boundary condition. Our result shows that the SO coupling can influence
the eigenenergy in a periodical pattern. The interplay between interaction and
SO coupling may induce the energy level crossing for the ground state, which
leads to a transition from the ferromagnetic to antiferromagnetic state.Comment: 6 pages, 4 figure
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