Lattice gauge theories and cold atomic mixtures

In the fundamental laws of physics, gauge fields mediate the interaction between charged particles. An example is quantum electrodynamics---the theory of electrons interacting with the electromagnetic field---based on U(1) gauge symmetry. Solving such gauge theories is in general a hard problem for classical computational techniques. While quantum computers suggest a way forward, it is difficult to build large-scale digital quantum devices required for complex simulations. In this talk, I will present our work on analog quantum simulators of a U(1) gauge theory in one spatial dimension. To engineer the local gauge symmetry, we employ inter-species spin-changing collisions in an atomic mixture. We demonstrate the experimental realization of the elementary building block and discuss how it can be scaled to a U(1) gauge theory in one spatial dimension.