Phase diagram of the double perovskite Sr₂CrReO₆: Effective-field theory

The double perovskite Sr₂CrReO₆ has very important characteristics for spintronic applications. It is a ferrimagnetic material distinguished by its high Curie temperature T_c≈635 K. We made this statistical study to further reveal the different ways in which this compound can behave with respect to interaction couplings and crystal fields prevailing in the system. We used as approximation an effective field theory (EFT) without correlation in the context of the Ising model. Thus we report different phase diagrams, firstly in relation to the exchange couplings present in the model adopted, and secondly in relation to the crystal fields of Cr and Re. We compare the results found by this method with those found by other statistical methods. Several phase transitions are detected and reentrant phenomenon was observed. - Highlights: • Phase diagram of double perovskite Sr₂CrReO₆ has been investigated • The phase diagrams depend on the exchange couplings and the crystal fields • Reentrant phenomenon has been observed