Magnetic and magnetocaloric properties of HoMn2O5single crystals were investigated. HoMn2O5 undergoes a large conventional magnetocaloric effect around 10 K. The magnetocaloric effect was found to present a giant anisotropy. Consequently, a large magnetocaloric effect (−ΔSR,max= 12.43 J/kg K for 7 T) can be obtained simply by rotating the single crystal HoMn2O5 within the cb plane in constant magnetic field instead of moving it in and out of the magnetic field zone. This can open the way for the implementation of compact, simplified, and efficient rotary magnetic refrigerators.

The authors thank M. Castonguay and S. Pelletier for technical support and S Mansouri for the Raman spectra of HoMn2O5. We acknowledge the financial support from NSERC (Canada), FQRNT (Québec), CFI, CIFAR, and the Université de Sherbrooke.