Abstract
Observation of significant negative exchange bias () is reported in solid solutions of single-phase samples of for and 1 with corresponding Néel temperatures at and 225 K, respectively, and the spin-reorientation transitions at 48 K, 58 K, and 38 K, respectively. In contrast, no was observed for the sample with (i.e., ) shows no below its , and no reorientation of spins at lower temperatures was observed. More importantly, the (negative) for the and 1 samples is observed only in the temperature range between and with the corresponding observation of magnetic coercivity. These results show that the canted antiferromagnetic structure of the moments present between and is essential for the observed . By comparing this result to the literature, common features of single-phase materials with were identified. The present bulk powder samples were prepared by the citrate method and structurally characterized by x-ray diffraction and Raman spectroscopy techniques. Neutron diffraction measurements for the and 1 samples at select temperatures were done to verify the presence of the structure between and and the structure (with no canting of moments) below .
3 More- Received 2 February 2016
- Revised 11 May 2016
DOI:https://doi.org/10.1103/PhysRevB.93.184430
©2016 American Physical Society