Dynamical control of matter-wave tunneling in periodic potentials

TL;DR

This paper demonstrates how strong sinusoidal shaking of an optical lattice can dynamically suppress or control matter-wave tunneling in a Bose-Einstein condensate, enabling potential quantum phase transition manipulation.

Contribution

It provides experimental evidence and theoretical validation for controlling tunneling in BECs via lattice shaking, a novel method for quantum state manipulation.

Findings

Tunneling rate can be reduced or suppressed by lattice shaking.

Phase coherence of BEC remains intact under strong shaking.

Experimental results agree with theoretical models.

Abstract

We report on measurements of dynamical suppression of inter-well tunneling of a Bose-Einstein condensate (BEC) in a strongly driven optical lattice. The strong driving is a sinusoidal shaking of the lattice corresponding to a time-varying linear potential, and the tunneling is measured by letting the BEC freely expand in the lattice. The measured tunneling rate is reduced and, for certain values of the shaking parameter, completely suppressed. Our results are in excellent agreement with theoretical predictions. Furthermore, we have verified that in general the strong shaking does not destroy the phase coherence of the BEC, opening up the possibility of realizing quantum phase transitions by using the shaking strength as the control parameter.