Multiple spin reorientation transitions in Ga-substituted DyCrO.

Single-phase DyCrGaO (0 ≤ ≤ 0.5) samples were synthesized successfully by a sol-gel method. Magnetic measurement results indicate that the Ga-substituted samples exhibit multiple spin reorientation transitions ( → → → ), whereas the pure DyCrO sample does not exhibit any spin reorientation transition. This is the first time that three types of spin reorientation transitions have been observed simultaneously in a rare-earth orthochromite sample. The stability of the spin reorientation transitions under cooling field was also investigated. Additionally, the temperature dependent inverse susceptibility exhibits a downward deviation from Curie-Weiss behavior above Néel temperature, suggesting the presence of the Griffiths phase in the Ga-substituted samples. The occurrence of such rich magnetic structures can be attributed to the fact that Ga substitution weakens the exchange interaction between Cr ions as well as between rare-earth ions (R) and Cr ions more effectively in DyCrO. Notably, Dy possesses the highest effective magnetic moment among all rare-earth ions, which may enhance the sensitivity of the magnetic properties to substitutions. The multiple spin reorientation transitions make DyCrGaO promising candidate materials for magnetic switching devices.