Unexpected magnetism, Griffiths phase, and exchange bias in the mixed lanthanidePr0.6Er0.4Al2

Abstract

We report an unusual coexistence of ferromagnetism and ferrimagnetism, and metamagnetism in ${\text{Pr}}_{0.6}$${\text{Er}}_{0.4}$${\text{Al}}_{2}$. In addition, this compound retains a clear Griffiths phase behavior even at 1 kOe magnetic field and shows a large exchange bias after field cooling from the paramagnetic state. The crystal-field excitations and opposite exchange interactions between nearest-neighbor and next-nearest-neighbor rare earth sites explain these behaviors.