Time reversal in an optical lattice

Time reversal is an oft-used technique to probe and measure a quantum system. In particular, it is key for some theoretical information approaches to quantum criticality like fidelity decay. Here proposed is how to reverse the dynamics of cold bosonic atoms in an optical lattice in the regime described by the Bose-Hubbard model. The proposed experiment uses proven techniques-a linear phase imprint on the lattice, and a change in magnetic field to tune the boson-boson scattering length through a Feshbach resonance. The sensitivity of quantum dynamics across the insulator-superfluid quantum phase transition of the Bose-Hubbard model is studied, and sensing applications of dynamic reversals such as measuring the intensity of external potentials (e.g., gravity) is discussed. (C) 2010 Optical Society of America