Microscopic dynamics of Bose atoms in a parabolic lattice

Andrey Kolovsky

Max-Planck-Institut für Physik komplexer Systeme

A.~R.~Kolovsky, A.~V.~Ponomarev, and A.~Buchleitner
We consider bosonic atoms in an anisotropic three dimensional optical lattice, created by standing laser waves with amplitudes V_z \ll V_x, V_y 30 E_R (E_R being the recoil energy). The strong transverse confinement of the atoms reduces the problem to that for a small ($N<50$) ensemble of Bose atoms in a 1D parabolic lattice. We study the dynamical response of the system to a sudden shift of the parabolic lattice center. In the single particle approach this responce would be either the dipole or Bloch oscillations of the atoms, depending on the shift magnitude. We analyze the effect of atom-atom interactions on these dynamical regimes of the system for arbitrary value of the microscopic interaction constant.