Relaxation dynamics in quantum gases

Activité scientifique

Our team studies the relaxation dynamics of quantum gases after a quench. According to the standard scenario, such dynamics should be driven by the propagation of quasi-particle pairs which manifest as two-point correlations propagating across the system. While this picture could be verified in several 1D systems, its validity remains unclear in 2D. In particular, the phase diagram of the 2D Bose-Hubbard model exhibits a quantum critical region where quasi-particles are expected to be short-lived, and the standard scenario may not apply. In order to observe and characterize the dynamics in this peculiar case, we have built a new apparatus which produces 2D ultracold ⁸⁴Sr gases in optical lattices, and features a high-resolution fluorescence microscopy imaging system enabling the direct measurement of two-point correlation functions.

Figure : A microscope objective and height electrodes inside our vacuum chamber (Marc CHENEAU, 2021).