Ultra-cold dipolar gases

TL;DR

This paper reviews the physics of ultra-cold dipolar gases, covering weakly interacting gases, strongly correlated phases, optical lattice behaviors, and potential applications in quantum memory and quantum Hall effects.

Contribution

It provides a comprehensive overview of recent theoretical developments in ultra-cold dipolar gases, highlighting new quantum phases and experimental possibilities.

Findings

Dipolar Bose-Einstein condensates show unique instabilities.

Optical lattices enable rich quantum phase structures.

Rotating dipolar gases may realize fractional quantum Hall states.

Abstract

We present a concise review of the physics of ultra-cold dipolar gases, based mainly on the theoretical developments in our own group. First, we discuss shortly weakly interacting ultra-cold trapped dipolar gases. Dipolar Bose-Einstein condensates exhibit non-standard instabilities and the physics of both Bose and Fermi dipolar gases depends on the trap geometry. We focus then the second part of the paper on strongly correlated dipolar gases and discuss ultra-cold dipolar gases in optical lattices. Such gases exhibit a spectacular richness of quantum phases and metastable states, which may perhaps be used as quantum memories. We comment shortly on the possibility of superchemistry aiming at the creation of dipolar heteronuclear molecules in lattices. Finally, we turn to ultra-cold dipolar gases in artificial magnetic fields, and consider rotating dipolar gases, that provide in our opinion the best option towards the realization of the fractional quantum Hall effect and quantum Wigner crystals.