Study of magnetic entropy and ESR in ferromagnet CuCr2Te4

Abstract The magnetic entropy around the critical temperature ( T C ) has been systematically investigated in CuCr 2 Te 4 . Reliable critical exponents β , γ and δ are obtained according to the magnetic field ( H ) dependence of magnetic entropy ( S M ) change | Δ S M | max ∝ H n with n = ( 1 + ( 1 / δ ) ) ( 1 − ( 1 / β ) ) and modified Arrott plot method. The critical exponents are found to obey the single scaling equation of M ( H , e ) = e β f ± ( H / e β + γ ) , where f ± is regular functions with f + for T > T C , f − for T T C, e is the reduced temperature ( T − T C )/ T C . It proves that the magnetic field dependence of magnetic entropy change is an effective and valid method to study the critical behavior in this kind of ferromagnet. Detailed analysis of the electron spin resonance experiment reveals that a strong spin–orbit coupling arises near T C in CuCr 2 Te 4 . This strong spin–orbit coupling may have a significant effect on the deviation of the exponents.