Magnetic resonance and spin-reorientation transitions in the Nd0.75Ho0.25Fe3(BO3)4 multiferroic

Abstract

A presentation of experimental study results obtained by antiferromagnetic resonance (AFMR) of the high-frequency properties of the multiferroic Nd 0.75 Ho 0.25 Fe 3 (BO 3 ) 4 in a broad range of temperatures and frequencies. We studied the effect of substituting the Nd 3þ ions with Ho 3þ , on the resonance properties of the Nd 0.75 Ho 0.25 Fe 3 (BO 3 ) 4 solid solution. In addition, we investigated the particularities of magnetic-field induced spin-reorientation phase transitions for Hjjc and Hjja directions, in which the anisotropy of the magnetic system is measured from "easy-axis" anisotropy to "easy-plane." The AFMR modes of a Fe 3þ subsystem are revealed. New information about the most important characteristics of AFM is obtained, including: frequency-field dependence of the AFMR spectrum, gaps in the spin-wave spectrum, effective magnetic anisotropy values, and fields of spin-reorientation transitions. It is shown that "easy-plane" anisotropy prevails in this magnet, with a weak anisotropy in the basal plane. For the first time there are observed features in the AFMR spectra that could be tied to the presence of a spatially modulated spin structure (incommensurate phase) in AFM Nd 0.75 Ho 0.25 Fe 3 (BO 3 ) 4 . V C 2015 AIP Publishing LLC.

Magnetic field tuning of the spin dynamics in the magnetic topological insulators (MnBi$_{2}$Te$_{4}$)(Bi$_{2}$Te$_{3}$)$_{n}$

“…6) can be due to the motion of the domain walls, which can cause spontaneous spin reorientation effect similar to Ref. [44]. The even more puzzling high-field jumps could, in turn, possibly result from some spin reorientation effect due to the proximity to the AFM-FM instability revealed in our HF-ESR experiments because the step-like change of the microwave signal occurs in the field range of the crossover from the AFM to the FM spin-polarized state (Figs.…”

“…The observed phenomenon is puzzling since no sharp anomalies in this field range were found in the static magnetization measurements for the H ab-plane geometry [24]. Similar step-like changes of the microwave signal S D (H) in small fields were observed in the antiferromagnetic rare-earth ferroborate Nd 0.75 Ho 0.25 Fe 3 (BO 3 ) 4 and attributed to the spin-reorientation phenomenon [44]. One can speculate that in the case of MnBi 2 Te 4 the jumps in the field range 0 − 1 T (Fig.…”

Magnetic-field tuning of the spin dynamics in the magnetic topological insulators(MnBi2Te4)(Bi2Te3)Alfonsov1, Mehlawat2, Zeugner3 et al. 2021Phys. Rev. B13020View full textAdd to dashboardCite

“…6) can be due to the motion of the domain walls, which can cause spontaneous spin reorientation effect similar to Ref. [45]. The even more puzzling high-field jumps could, in turn, possibly result from some spin-reorientation effect due to the proximity to the AFM-FM instability revealed in our HF-ESR experiments because the steplike change of the microwave signal occurs in the field range of the crossover from the AFM to the FM spin-polarized state (Fig.…”

“…The observed phenomenon is puzzling since no sharp anomalies in this field range were found in the static magnetization measurements for the H ab-plane geometry [24]. Similar steplike changes of the microwave signal S D (H ) in small fields were observed in the AFM rare-earth ferroborate Nd 0.75 Ho 0.25 Fe 3 (BO 3 ) 4 and attributed to the spinreorientation phenomenon [45]. One can speculate that in the case of MnBi 2 Te 4 the jumps in the field range 0 − 1 T (Fig.…”