Elastocaloric Measurements of Quantum Materials—The Case of TmVO₄ and the Prospect of Cryogenic Elastocaloric Cooling

We have developed an AC method to probe the elastocaloric effect and have applied it to a variety of quantum materials. The technique can be used to study the entropy landscape associated with continuous phase transitions, but is especially useful for the study of materials for which strain couples to order parameter fluctuations in non-trivial ways. In particular, I will discuss the elastocaloric signature of nematic fluctuations, and the observation of a giant elastocaloric effect in TmVO₄, a material that provides a prototypical example of the cooperative Jahn-Teller effect at low temperature.