Observation of interaction-driven dynamical delocalization of the 3D Anderson insulator*

The quantum kicked rotor (QKR) is a paradigmatic system to study the Anderson model. The 3D Anderson model is known to display a metal-insulator transition. However, the addition of interaction to the 3D Anderson model has remained unexplored experimentally. We report on our observation of interaction-driven dynamical delocalization of the 3D Anderson insulator. We load a ¹⁷⁴Yb BEC into 1D tubes formed by a two-dimensional optical lattice. We then pulse on a one-dimensional lattice with a fixed kick period along the axial direction of the tubes. The pulse amplitude is modulated by two incommensurate frequencies to simulate the 3D Anderson model. We measure the energy of the system by analyzing the momentum profile of the atom cloud after some number kicks. We study the delocalization of the 3D Anderson insulator for different interaction strengths, kick strengths, and modulation amplitudes, and measure the power-law exponent. Our experiment sheds light on the transport dynamics in a disordered medium in the presence of interaction.