arXiv:1203.5033 · Physical Review A
Coherent destruction of tunneling of two interacting bosons in a tight-binding lattice
Stefano Longhi, Giuseppe Della Valle
Abstract
The dynamics of two correlated bosons hopping on a one-dimensional lattice and driven by a sinusoidal force is analytically investigated by means of a multiple-time-scale asymptotic analysis of the driven Bose-Hubbard Hamiltonian. By assuming the ratio $\ensuremath{\epsilon}=J/\ensuremath{\omega}$ between the tunneling rate $J$ and modulation frequency $\ensuremath{\omega}$ of the driving field as a small parameter, the perturbative analysis shows that, under appropriate driving conditions, coherent destruction of tunneling can be simultaneously realized for both paired and unpaired states up to the long time scale $\ensuremath{\sim}$$1/(\ensuremath{\omega}{\ensuremath{\epsilon}}^{2})$ in the regime corresponding to an energy quantum $\ensuremath{\hbar}\ensuremath{\omega}$ of the driving field of the same order of magnitude as the particle interaction energy $\ensuremath{\hbar}{U}_{0}$. The predictions of the perturbative analysis are confirmed by direct numerical simulations of the two-particle Bose-Hubbard Hamiltonian and by direct quasienergy-band computation.