Role of rare earth ions in the magnetic, magnetocaloric and magnetoelectric properties of RCrO3 (R = Dy, Nd, Tb, Er) crystals†
We report a systematic study on the magnetic, magnetocaloric (MC), specific heat and magnetoelectric (ME) properties of the single crystals of rare-earth orthochromites, RCrO3 (R = Dy, Nd, Er, Tb). Interesting stair-like metamagnetic transitions were observed for the first time in TbCrO3 crystals. Intrinsic large anisotropy in the magnetic and ME properties were also revealed in all of the RCrO3 crystals. The reorientation/ordering of the rare earth R3+ spins was observed to be accompanied with large MC, rotating MC and ME effects. These behaviors are found be closely related to the R–R and R–Cr interactions in these chromites. In particular, the ME effect can be ascribed to the spin–phonon coupling. All these results suggest the essential and unique role of 4f electrons of rare earth ions in these chromites.