The effect of defects formed under pressure on CuCrO2 delafossite

Abstract

Pressure-dependent delafossite CuCrO2 samples are synthesized by the solid-state reaction method to investigate the effect of defects formed under pressure on the structure and magnetic properties of CuCrO2. X-ray Diffractometer, Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), Photoluminescence spectroscopy (PL), and Vibrating Sample Magnetometer (VSM) are used the characterize CuCrO2 samples. All samples give almost the same structural phase properties without any secondary peaks. All magnifications of SEM images show no melting of the sample and thus the annealing temperature of the samples is optimized. Photoluminescence measurements reveal that near band emission is caused by excitonic transitions between electrons and holes, the stronger the UV emission of the sample, the higher the crystallization quality, and fewer defects occur. Magnetic investigations depict that the spins are antiferromagnetically oriented while they have a magnetic moment component perpendicular to the plane. Therefore, each grain should be considered a weak magnet. Temperature-dependent magnetic moment measurements exhibit a slight variation in moment values. The reason behind this should be attributed to the grain size related to the formation of grains by applied pressure.