Study of spin-phonon coupling and magnetic field induced spin reorientation in polycrystalline multiferroic $GdFeO_3$

TL;DR

This study investigates the spin-phonon coupling and magnetic field-induced spin reorientation in polycrystalline GdFeO3, revealing phase purity, spin reorientation under magnetic field, and structural changes across the Neel temperature.

Contribution

It provides new insights into the magnetic and structural properties of GdFeO3, including field-induced spin reorientation and spin-phonon interactions, using multiple spectroscopic and diffraction techniques.

Findings

Field-induced spin reorientation observed via Mössbauer spectroscopy.

Neel temperature determined as 672.5 K with a critical exponent of 0.333.

Signatures of spin-phonon coupling and structural re-arrangement across T_N.

Abstract

The present work reports the preparation of polycrystalline multiferroic $GdFeO_3$ (GdFO) and characterization with x-ray diffraction (XRD), magnetization, temperature dependent Raman spectroscopy, temperature and magnetic field dependent $^{57}Fe$ M$\ddot{o}$ssbauer spectroscopy measurements. The sample is found to be phase pure from Rietveld refinement of XRD pattern. The M$\ddot{o}$ssbauer spectra measured in the presence of external magnetic field show the signatures of field induced spin reorientation transition, which are corroborated by magnetization measurements. From the temperature dependent variation of internal hyperfine field, N$\grave{e}$el transition temperature ($T_{N,Fe}$) of 672.5$\pm$0.2 K and critical exponent ($\beta$) of 0.333$\pm$0.003 is obtained. Temperature dependent (300 - 760 K) Raman spectroscopy measurements show the signatures of spin-phonon coupling and local structural re-arrangement across $T_{N,Fe}$.