Cooling by adiabatic application of pressure - the barocaloric effect

A never principle for cooling by adiabatic pressure-application is introduc ed. A pressure induced structural and/or magnetic phase transition is used to change the degeneracy of the crystal-held ground state. The resulting ch ange in entropy can then be used to achieve adiabatic cooling in a similar way to the well-known cooling by adiabatic demagnetization as will be demon strated for the rare-earth compound Ce1-x(LayY1-y)(x)Sb. So far cooling rat es of 2K per 0.52 GPa pressure change at 20 K could be achieved in CeSb. Du e to the lack of measurements of the specific heat under pressure we reveal quantitative information on the cooling mechanism by elastic and inelastic neutron scattering measurements. (C) 2000 Elsevier Science B.V. All rights reserved.