Manifestation of magnetoelastic interactions in Raman spectra of Ho_xNd1−_xFe₃(BO₃)₄ crystals

Abstract

Raman spectra of Ho[Formula: see text]NdxFe(BO3)4 ([Formula: see text], 0.75, 0.5, 0.25) have been studied in temperature range 10–400[Formula: see text]K. Two compositions ([Formula: see text], [Formula: see text]) demonstrate structural phase transition with soft mode restoration. The addition of Nd atoms increases interatomic spacing and decreases the temperature of structural phase transition. The solid solutions ([Formula: see text], 0.5, 0.25) demonstrate the emergence of the peaks corresponding to magnetoelastic interaction below Néel temperature. The order parameter of the magnetic phase transition has been determined. The equal concentrations of holmium and neodymium atoms prevent magnon soft modes condensation caused by exchange interactions in Fe–O–Fe chains are observed. Calculations confirm the data obtained in the experiment.

Сравнение спектров поглощения ионов Nd-=SUP=-3+-=/SUP=- в кристаллах NdFe-=SUB=-3-=/SUB=-(BO-=SUB=-3-=/SUB=-)-=SUB=-4-=/SUB=-, Nd-=SUB=-0.5-=/SUB=-Gd-=SUB=-0.5-=/SUB=-Fe-=SUB=-3-=/SUB=-(BO-=SUB=-3-=/SUB=-)-=SUB=-4-=/SUB=- и Ho-=SUB=-0.75-=/SUB=-Nd-=SUB=-0.25-=/SUB=-Fe-=SUB=-3-=/SUB=-(BO-=SUB=-3-=/SUB=-)-=SUB=-4-=/SUB=-

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“…Для полноты картины на рис. 9 представлено изменение положения линии структурной мягкой моды в кристалле Ho 0.75 Nd 0.25 Fe 3 (BO 3 ) 4 в зависимости от температуры, взятое из работы [15]. Изменение положения мягкой моды также происходит скачком.…”

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Predicted strong spin-phonon interactions in Li-doped diamond

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