The behavior of many interacting quantum particles is at the heart of some of the richest most puzzling phenomena in modern physics, such as the mechanism of high-Tc superconductivity, the microscopics of the ν=5/2 fractional quantum Hall state, or the phase diagram of quantum chromodynamics. This so-called quantum many-body problem is encountered across a wide range of energy scales, from the quark-gluon plasma (at temperatures 1012K), down to superfluid helium (100K), and ultracold gases (10-9K). It is extremely difficult to tackle with classical computers, and the past decade has witnessed an exploding interest in an alternative path: devising well-controlled quantum systems that can be used to investigate prototypical quantum many-body models, a program known as quantum simulation.
Figure 1: Cartoon of atoms (blue) trapped in a box of light made of repulsive (green) laser beams.
Ultracold quantum matter is a fascinating platform to conduct this program. We can control the laser traps in which the atoms are confined, the interactions between particles, or subject them to effective gauge fields. These ultracold atoms offer a “magnifying glass” to study phenomena that are hard to measure in other many-body systems. For instance, while inter-particle spacing in an electron gas is at the angstrom scale, our atoms are typically separated by micron-scale distances, making it relatively easy to probe our ultracold quantum matter down to the single particle constituent. Out-of-equilibrium solid-state systems often relax on very short time scales (femtoseconds or less). In our ultracold matter, out-of-equilibrium states can persist for much longer times (sometimes seconds), offering a new window on the poorly understood territory of far-from-equilibrium quantum dynamics.
|Figure 2: Example of a light pattern obtained using a digital micromirror device.
Recently, electro-optic devices have emerged as a remarkable technology to take quantum simulation to a new level with ultracold atoms. It is possible to use these devices to shape light in a programmable and dynamic manner. The resulting engineered potentials can be used to design ultracold quantum matter with pristine freedom. We will exploit these new tools to investigate homogeneous-density fermionic matter, new regimes of trapped-atom interferometry and far-from-equilibrium turbulent dynamics that could not have been accessed before.