Correlated temperature and field dependent magnetization: Enhanced magnetic hysteresis upon Dy doping in La-based francisite Cu3La(SeO3)2O2Cl

Abstract

Study of La-based cuprate francisite (LaCufr), an analogue compound of Cu3Bi(SeO3)2O2Cl, is interesting due to the interplay of competing magnetic interactions in this geometrically frustrated layered compound. The motivation is to investigate the role of rare earth metals with 4f electrons on Cu2+ ions with 3d electrons, i.e., to study a complex 3d-4f interaction. In this regard, pristine, 5, and 10 at% (atomic percentage) Dy doped La-based cuprate francisite [Cu3La1-xDyx(SeO3)2O2Cl; x = 0, 0.05, and 0.1] compounds were synthesized. Structural (X-ray diffraction i.e. XRD), electronic (X-ray absorption near edge structure i.e. XANES) and magnetic properties were investigated. XRD and XANES ensure phase purity and indicate dopant Dy atoms are more or less substitutionally incorporated at the La site. Magnetic properties were highlighted by unconventional magnetic hysteresis due to spin reorientation transition (SRT) and field-induced meta-magnetic transition (MMT) below 15 K. The signature of MMT was also observed from a temperature dependent magnetization (M−T) study, which is unique. The process of field dependent magnetization has been explored with a spin flop and spin flip transition. Dy doping enhances hysteresis and overall magnetization. The reason for this enhancement has been interpreted as identifying micro-interactions using an energy splitting scheme.