EFFECT OF THE GAS MEDIA AND TEMPERATURE REGIMES OF ANNEALING ON THE PHASE COMPOSITION OF IRON BORATE FeBO3

Iron borate FeBO3 crystals are annealed in neutral, oxidizing, and reducing gas media on a specially designed setup. The effect of the chemical medium and annealing modes on the surface morphology and phase composition of the samples is established.Исследования выполнены при финансовой поддержке РФФИ, проект № 19-29-12016-мк, в части разработки экспериментальной установки и получения кристаллических образцов. Рентгеновские и электронно-микроскопические измерения проведены при под-держке Министерства науки и высшего образования РФ в рамках выполнения работ по Государственному заданию ФНИЦ «Кристаллография и фотоника» с использованием оборудования ЦКП (проект RFMEFI62119X0035)

Anisotropic energy gap of low-frequency AFMR mode in Fe x Ga 1-x BO 3 single crystals

International audienc

Iron borate films: Synthesis and characterization

We report the first successful synthesis of iron borate films. FeBO 3 films on GaBO 3 single crystal sub strates have been prepared by a liquid phase epitaxy route. In order to determine optimal crystallization regimes, a series of experiments has been carried out. Electron microscope studies have allowed mon itoring different phases of the film formation. The compositions of the film and of the substrate have been determined by energy dispersive spectroscopy. X ray diffraction analysis has allowed an accurate determination of a mismatch between the lattice parameters of the film and of the substrate. Electron magnetic resonance studies of the FeBO 3 film confirm the existence of magnetic ordering. The values of the effective Dzyaloshinskii field as well as the Néel temperature are in good accordance with those previously determined for FeBO 3 single crystal

Exchange energy in diamagnetically diluted iron borate-based crystals

International audienc

Electron magnetic resonance of iron-gallium borate single crystals

Electron magnetic resonance (EMR) studies of iron-gallium borate, FexGa1−xBO3, single crystals have been carried out in the frequency range ca. 8–38 GHz in magnetizing fields up to 10 kOe and the temperature range of 4–310 K. With decreasing x in the range of 0.34≤x≤1, the EMR spectra show a gradual passage from a low-frequency antiferromagnetic resonance (AFMR) mode at x = 1 toward a coexistence of AFMR and cluster magnetic resonance arising, respectively, from completely and partially magnetically ordered crystal regions. Temperature and concentration dependences of magnetic characteristics of iron-gallium borates, namely, the Néel temperature, the Dzyaloshinskii–Moriya field, and the isotropic energy gap, have been determined by means of AFMR. In contrast to unmixed FeBO3, FexGa1−xBO3 crystals with 0.34≤x≤0.85 show anomalous nonmonotonic temperature dependences of the Dzyaloshinskii–Moriya field with a maximum well below the Néel temperature suggesting the occurrence of another magnetic transition in this temperature range