Analysis of the Anisotropic Magnetocaloric Effect in RMn2O5 Single Crystals

TitleAnalysis of the Anisotropic Magnetocaloric Effect in RMn2O5 Single Crystals
Publication TypeJournal Article
Year of Publication2017
AuthorsBalli, M, Mansouri, S, Jandl, S, Fournier, P, Dimitrov, DZ

Thanks to the strong magnetic anisotropy shown by the multiferroic RMn2O5 (R = magnetic rare earth) compounds, a large adiabatic temperature change can be induced (around 10 K) by rotating them in constant magnetic fields instead of the standard magnetization-demagnetization method. Particularly, the TbMn2O5 single crystal reveals a giant rotating magnetocaloric effect (RMCE) under relatively low constant magnetic fields reachable by permanent magnets. On the other hand, the nature of R3+ ions strongly affects their RMCEs. For example, the maximum rotating adiabatic temperature change exhibited by TbMn2O5 is more than five times larger than that presented by HoMn2O5 in a constant magnetic field of 2 T. In this paper, we mainly focus on the physics behind the RMCE shown by RMn2O5 multiferroics. We particularly demonstrate that the rare earth size could play a crucial role in determining the magnetic order, and accordingly, the rotating magnetocaloric properties of RMn2O5 compounds through the modulation of exchange interactions via lattice distortions. This is a scenario that seems to be supported by Raman scattering measurements.