Magnetism, spintronics

Resonant studies of the effect of Bi$^{3+}$ impurity on magnetic anisotropy and phase diagrams in gadolinium ferroborate GdFe$_3$(BO$_3$)$_4$

A. I. Pankrats^a, S. A. Skorobogatov^ab, I. N. Horoshiy^a, S. M. Zharkov^ab, G. M. Zeer^b, I. A. Gudim^a, V. R. Titova<sup>a

a</sup> L. V. Kirensky Institute of Physics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk
^b Siberian Federal University, Krasnoyarsk

Abstract: The resonant properties of gadolinium ferroborate GdFe$_3$(BO$_3$)$_4$ single crystals of varying quality are compared: nominally pure and those containing Bi$^{3+}$ ion impurities. The EDS method determined that the actual bismuth impurity content is close to the previously estimated 6% based on magnetic studies. The resonance properties confirm that both crystals form similar magnetic phase diagrams with an orientational transition between easy-axis and easy-plane antiferromagnetic ordering, which occurs either as a spontaneous transition at temperature $T_{SR}$ or as a transition to a magnetic field-induced easy-plane state at $T<T_{SR}$. Temperature dependencies of the effective magnetic anisotropy fields and the magnetoanisotropic contributions of the iron and gadolinium subsystems are calculated from the resonance data. It is concluded that the Bi$^{3+}$ ion impurity not only suppresses the contribution of the gadolinium subsystem, which these ions partially replace, but also causes a reduction in the contribution of the iron subsystem. As a result, the total change in the effective anisotropy field of the crystal is rather weak.

Keywords: magnetic anisotropy, resonance properties, magnetic phase diagrams, rare-earth ferroborates.

Received: 11.07.2025
Revised: 01.10.2025
Accepted: 13.10.2025

DOI: 10.61011/FTT.2025.11.62135.186-25

Bibliographic databases:

•