Co magnetic instability study in RCo3 by XMCD

Abstract We have performed a temperature-dependent study of the Er L3 and Co K edge X-ray magnetic circular dichroism (XMCD) in a (Er, Y)Co3 system. The Co K XMCD signal shows a clear change at 35 K, which has been associated to a Co metamagnetic transition, previously reported. However, around the compensation temperature Tcom, no discontinuity is observed, as should be expected if the magnetic moments were just reversed. The observed smooth passage through Tcom is interpreted as a transition from a collinear to a non-collinear Co ordering, where Co moments assume intermediate orientations. The analysis of the E2/E1 ratio has allowed us to gain some insight into the magnetic properties of the 5d band. Finally, from our XMCD measurements, it is possible to complete the magnetic phase diagram of (Er, Y)Co3, previously proposed.