title: (Magneto)caloric refrigeration: is there light at the end of the tunnel?
abstract: Caloric cooling and heat pumping rely on reversible thermal effects triggered in solids by magnetic, electric or stress fields. In the recent past, there have been several successful demonstrations of using first-order phase transition materials in laboratory cooling devices based on both the giant magnetocaloric and elastocaloric effects. All such materials exhibit non-equilibrium behaviours when driven through phase transformations by corresponding fields. Common wisdom is that non-equilibrium states should be avoided; yet, as we show using a model material exhibiting a giant magnetocaloric effect, non-equilibrium phase-separated states offer a unique opportunity to achieve uncommonly large caloric effects by very small perturbations of the driving field(s).This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.
authors.affiliation: Ames Laboratory, and Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-3020, USA vitkp@ameslab.gov.
authors.forename: Vitalij K
authors.identifier: 0000-0001-9503-7567
authors.initials: VK
authors.lastname: Pecharsky
authors.affiliation: Ames Laboratory, and Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-3020, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Cui
authors.affiliation: Ames Laboratory, and Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-3020, USA.
authors.forename: Duane D
authors.initials: DD
authors.lastname: Johnson
keywords: caloric cooling; caloric heat pumping; caloric materials; elastocaloric effect; electrocaloric effect; magnetocaloric effect