Quantum droplets and supersolidity in a magnetic superfluid

Speaker: Professor Blair Blakie
Affiliation: University of Otago

Abstract

Dilute magnetic superfluids are routinely produced in labs by cooling gases of the highly-magnetic lanthanides (bosonic isotopes of Er or Dy) into the ultra-cold regime. These systems exhibit long-ranged dipole-dipole interactions in additional to the usual short-ranged contact interactions. At the level of meanfield theory these gases are expected to be mechanically unstable to collapse when the short-ranged interactions are tuned to be weaker than the long-ranged interactions. Surprisingly experiments venturing into this regime have instead uncovered new types of behaviour: (i) self-bound quantum droplets, which persist in the absence of any container; (ii) a supersolid state of matter which possess both superfluid and crystalline order. In this talk I will give an overview of the basic physics of this system, a review of some of the main experimental developments, and outline of some of the related theoretical research in this area undertaken by my group.