Optical Investigations of YbCrO3. II. Metamagnetic Transition in YbCrO3

Abstract

R exciton lines of YbCrO 3 corresponding to the 4 A 2 g → 2 E g transition of Cr 3+ have been measured at 4.2 K, where a first order phase transition induced by magnetic field H 0 (// a )∼67 kOe has been found. We concluded that this phase transition is a metamagnetic transition at which ths weak ferromagnetic moment of the Cr 3+ spins reverses its coupling with the magnetic moment of the Yb 3+ spins from antiparallel to parallel. By the analysis of the spectral changes in the metamagnetic transition, the molecular field upon the Cr 3+ ion due to the Cr–Yb magnetic interaction was estimated. Generally, if the mnagnetic moment of the rare-earth spins couples antiparallel to the weak ferromagnetic moment of the transition-metal spins for other orthochromites and orthoferrites, the metamagnetic transition of this type will be expected.