Antiferromagnetic resonance and magnetic anisotropy in PrxY1-x Fe3(BO3)4 crystals in the region of the magnetic structure transformation easy axis - easy plane

The spin dynamics, magnetic structures and magnetic anisotropy of single crystals PrxY1-xFe3(BO3)(4) have been studied using antiferromagnetic resonance (AFMR) in a wide range of frequencies, magnetic fields, and temperatures. The frequency-field dependences of AFMR for the crystals with x = 0.25 and 0.45 are characteristic of antiferromagnets with the easy plane (EP) anisotropy. The crystals with x = 0.75 and 1.0 exhibit frequency-field dependences that are typical for antiferromagnets with the easy axis (EA) anisotropy. In these crystals, a significant decrease in the effective anisotropy fields of praseodymium upon the transition to the spin-flop state has been found. It is shown that this is the main reason for the large lability intervals, within which the regions of coexistence of the collinear and spin-flop states overlap. In the crystal with x = 0.67, the magnetic field applied along the trigonal axis of the crystal leads to the spin reorientation transition from the EA to the EP state. A magnetic phase diagram of the states on the plane magnetic field - temperature is built. In this crystal, the effective anisotropy field of praseodymium also decreases upon the transition to the field-induced EP state. Diamagnetic dilution of the praseodymium subsystem leads to the contribution of this subsystem to the total anisotropy field depending almost linearly on the praseodymium concentration. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study investigates the spin dynamics, magnetic structures, and magnetic anisotropy of single crystals PrxY1-xFe3(BO3)(4) using antiferromagnetic resonance (AFMR). The results show that the crystals exhibit either easy plane or easy axis anisotropy depending on the doping ratio, and the effective anisotropy field of praseodymium significantly decreases during the transition. A magnetic phase diagram is constructed, and the dilution of the praseodymium subsystem leads to a linear contribution to the total anisotropy field.