The weakening of fermionization of one dimensional spinor Bose gases induced by spin-exchange interaction

We investigate the ground state density distributions of anti-ferromagnetic spin-1 Bose gases in a one dimensional harmonic potential in the full interacting regimes. The ground state is obtained by diagonalizing the Hamiltonian in the Hilbert space composed of the lowest eigenstates of noninteracting Bose gas and spin components. The study reveals that in the situation of a weak spin-dependent interaction the total density profiles evolve from a Gaussian-like distribution to a Fermi-like shell structure of N peaks with the increasing of spin-independent interaction. The increasing spin-exchange interaction always weakens the fermionization of the density distribution such that the total density profiles show the shell structure of less peaks and even show single peak structure in the limit of the strong spin-exchange interaction. The weakening of fermionization results from the formation of composite atoms induced by the spin-exchange interaction. It is also shown that phase separation occurs for the spinor Bose gas with a weak spin-exchange interaction, meanwhile the spin-independent interaction is strong.