Strongly Correlated Quantum Walks in Optical Lattices

Philipp M. Preiss, Ruichao Ma, M. Eric Tai, Alexander Lukin, Matthew
Rispoli, Philip Zupancic, Yoav Lahini, Rajibul Islam, and Markus Greiner

Full control over the dynamics of interacting, indistinguishable quantum particles is an important prerequisite for the experimental study of strongly correlated quantum matter and the implementation of high- delity quantum information processing. Here we demonstrate such control over the quantum walk – the quantum mechanical analogue of the classical random walk – in the strong interaction regime. We directly observe fundamental e ects such as the emergence of correlations due to quantum statistics and interactions in two-particle quantum walks, as well as strongly correlated Bloch oscillations in tilted optical lattices. Our approach can be scaled to larger systems, greatly extending the class of problems accessible via quantum walks, which can now serve as a basis for universal quantum computation and as a quantum simulator for strongly correlated many-body dynamics.