Temperature dependent electron paramagnetic resonance study on magnetoelectric YCrO3

Abstract

We report temperature dependent electron paramagnetic resonance (EPR) studies on polycrystalline YCrO3 samples at X-band (9.46 GHz) in the temperature range of 120 K–298 K. The EPR spectra exhibit a single broad line across the whole temperature range, attributed to Cr3+ ions. The variation of EPR spectra parameters (line width, integrated intensity, and g-factor) as a function of temperature was analyzed to understand the nature of spin-dynamics in the paramagnetic region of YCrO3. A peak in the g-factor suggests the presence of a new phase within the paramagnetic state at an intermediate point of temperature TIP ~ 230 K, attributed to the onset of short range canted antiferromagnetic correlations in the material much above 140 K, Néel temperature (TN) of YCrO3. The EPR intensity increases with a decrease in temperature up to TN due to the renormalization of the magnetic moments arising from the appearance of canted antiferromagnetic correlations. Further, temperature dependent dielectric measurements also exhibit an anomaly at ~230 K suggesting the presence of magnetodielectric coupling in YCrO3, with a possibility towards a relatively high temperature magnetodielectric system.