Effect of Magnetic Vacancies on the Spontaneous Spin-Reorientation Transition in HoFe$_{1-x}$Al$_x$O$_3$ Single Crystals

S. A. Skorobogatov; V. A. Babkina; M. S. Pavlovskii; M. I. Kolkov; S. V. Semenov; I. N. Khoroshiy; S. E. Nikitin; K. A. Shaykhutdinov

arXiv · 2608.16348

Effect of Magnetic Vacancies on the Spontaneous Spin-Reorientation Transition in HoFe$_{1-x}$Al$_x$O$_3$ Single Crystals

S. A. Skorobogatov·V. A. Babkina·M. S. Pavlovskii·M. I. Kolkov·S. V. Semenov·I. N. Khoroshiy·S. E. Nikitin·K. A. Shaykhutdinov

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Abstract

In this work, we report the first growth of single crystals of the substitution series HoFe$_{1-x}$Al$_x$O$_3$ with aluminium concentrations up to $x=0.2$ and investigate the evolution of their spontaneous spin-reorientation transition (SRT). Among rare-earth orthoferrites, HoFeO$_3$ exhibits a distinctive sequence of magnetic phases ($\Gamma_4$-$\Gamma_{24}$-$\Gamma_{12}$-$\Gamma_2$). This complex sequence arises from the competition between the $K_{ac}$ and $K_{ab}$ anisotropies associated with the Ho$^{3+}$ ions and the effective magnetic field produced by the weak ferromagnetic moment of the canted Fe$^{3+}$ sublattice. Introducing magnetic vacancies perturbs the antiferromagnetic compensation of the Fe$^{3+}$ subsystem in the $ab$ plane and generates an additional effective magnetic field acting on the Ho$^{3+}$ ions. This field alters the balance between the $K_{ac}$ and $K_{ab}$ anisotropies within the SRT temperature range and thereby broadens the stability range of the $\Gamma_{12}$ phase in the magnetic phase diagram.

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S. A. Skorobogatov, V. A. Babkina, M. S. Pavlovskii, M. I. Kolkov, S. V. Semenov, I. N. Khoroshiy, S. E. Nikitin, K. A. Shaykhutdinov. 2026-08-17. Effect of Magnetic Vacancies on the Spontaneous Spin-Reorientation Transition in HoFe$_{1-x}$Al$_x$O$_3$ Single Crystals. https://arxiv.org/abs/2608.16348

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