We investigate the thermodynamics of one-dimensional (1D) Bose gases in the strongly correlated regime. To this end, we prepare ensembles of independent 1D Bose gases in a two-dimensional optical lattice and perform high-resolution in situ imaging of the column-integrated density distribution. Using an inverse Abel transformation we derive effective one-dimensional line-density profiles and compare them to exact theoretical models. The high resolution allows for a direct thermometry of the trapped ensembles. The knowledge about the temperature enables us to extract thermodynamic equations of state such as the phase-space density, the entropy per particle, and the local pair-correlation function.We investigate the thermodynamics of one-dimensional (1D) Bose gases in the strongly correlated regime. To this end, we prepare ensembles of independent 1D Bose gases in a two-dimensional optical lattice and perform high-resolution in situ imaging of the column-integrated density distribution. Using an inverse Abel transformation we derive effective one-dimensional line-density profiles and compare them to exact theoretical models. The high resolution allows for a direct thermometry of the trapped ensembles. The knowledge about the temperature enables us to extract thermodynamic equations of state such as the phase-space density, the entropy per particle, and the local pair-correlation function.

arXiv:1304.4625Physical Review ASep 11, 201354 citations

Effect of dipole-dipole interaction on unpolarized ultracold fermionic gases in a two-dimensional optical lattice

Takayuki Watanabe

We study effects of the dipole-dipole interaction on fermionic cold atomic gases in two-dimensional optical lattice. We calculate spin and density correlation functions within the random-phase approximation. It is shown that the spin-correlation functions of spin components perpendicular to the lattice plane show a characteristic peak structure different from that of the parallel component. We study $s$ -wave and $d$ -wave superfluidity induced by the spin and density correlations and show that the dipole-dipole interaction assists the $d$ -wave superfluidity.We study effects of the dipole-dipole interaction on fermionic cold atomic gases in two-dimensional optical lattice. We calculate spin and density correlation functions within the random-phase approximation. It is shown that the spin-correlation functions of spin components perpendicular to the lattice plane show a characteristic peak structure different from that of the parallel component. We study $s$-wave and $d$-wave superfluidity induced by the spin and density correlations and show that the dipole-dipole interaction assists the $d$-wave superfluidity.

Physical Review ANov 23, 20098 citations

Dynamics and correlations in one-dimensional gases

Dimitri M. Gangardt

Bulletin of the American Physical SocietyMay 18, 20060 citations

Correlation effects on atom-density profiles of one- and two-dimensional polarized atomic Fermi gases loaded on an optical lattice

Masahiko Machida, S. Yamada, Masahiko Okumura +2 more

We investigate effects of optical lattice potential in one- and two-dimensional two-component trapped Fermi gases with population imbalances. Using the exact diagonalization and the density matrix renormalization group methods complementarily, we calculate the atom-density profile from the ground state many-body wave function as a function of attractive interaction strength for various population imbalances. The numerical results reveal that although a phase separation between the superfluid core and the shell cloud of excess atoms occurs as observed in experiments without the optical lattice, the population imbalance generally remains in the core region in contrast to the nonlattice cases. The essence of the numerical results in a strong attractive regime can be explained by an effective model composed of Cooper pairs and excess major fermions.We investigate effects of optical lattice potential in one- and two-dimensional two-component trapped Fermi gases with population imbalances. Using the exact diagonalization and the density matrix renormalization group methods complementarily, we calculate the atom-density profile from the ground state many-body wave function as a function of attractive interaction strength for various population imbalances. The numerical results reveal that although a phase separation between the superfluid core and the shell cloud of excess atoms occurs as observed in experiments without the optical lattice, the population imbalance generally remains in the core region in contrast to the nonlattice cases. The essence of the numerical results in a strong attractive regime can be explained by an effective model composed of Cooper pairs and excess major fermions.

arXiv:0806.0465Physical Review AMay 28, 200816 citations

s

-wave and

d

-wave superfluidity induced by the spin and density correlations and show that the dipole-dipole interaction assists the

d

-wave superfluidity.