Decoherence in Long-Lived Bloch Oscillation

He Yang, Fusheng Liu, Guangjiong Dong

Long Wang, Zi-Fa Yu, Ju-Kui Xue

Within the mean-field model, the coherent matter waves of a dipolar condensate in a harmonic potential superimposed to a deep lattice are investigated by the variational principle. It is shown that, in a harmonic potential superimposed to a deep lattice, it is possible to control the decoherence of Bloch oscillations due to the fact that the on-site and the inter-site dipolar interactions can not only damp out Bloch oscillations but also maintain long-lived Bloch oscillations under the certain condition. In particular, long-lived Bloch oscillations of dipolar condensate can be realized when the dipolar interaction, the contact interaction, the frequency of the harmonic potential and initial width of the wave packet satisfy an analytical condition. Thus the decoherence of Bloch oscillation can be controlled by adjusting the dipolar interaction, the contact interaction, the frequency of harmonic potential and the initial width of the wave packet.

J. C. Retamal

Huai-Qiang Gu, Jun-Hong An, Kang Jin

We study the Bloch oscillations (BOs) of two-component Bose-Einstein condensates (BECs) trapped in spin-dependent optical lattices. Based on the derived equations of motion of the wave packet in the basis of localized wave functions of the lattice sites, the damping effect induced by the intercomponent and intracomponent interactions to the BOs is explored analytically and numerically. We also show that such damping of the BOs can be suppressed entirely if all the atom-atom interactions are modulated synchronously and harmonically in time with suitable frequency via the Feshbach resonance. When the intercomponent and the intracomponent interactions have inverse signs, we find that the long-living BOs and even the revival of the BOs can be achieved via only statically modulating the configuration of optical lattices. The results provide a valuable guidance for achieving long-living BOs in the two-component BEC system by the Feshbach resonances and manipulating the configuration of the optical lattices.

Masudul Haque

M. A. de Ponte, M. C. de Oliveira, M. H. Y. Moussa