Scaling study of the magnetic entropy change in room-temperature ferromagnet Cr3Te4

Abstract

The intrinsic room-temperature ferromagnetism, stability in air, and easy tunability make chromium telluride Cr3Te4 a material with great promise for application in spintronics. This study investigates the magnetic entropy change (ΔSM) associated with critical exponents of Cr3Te4 single crystal. Temperature-dependent ΔSM suggests a drastic entropy change caused by the transition, the parameters of which show field-dependent power-law behaviors. Fitting the ΔSM(T,H) parameters yields critical exponents α=0.056(9), β=0.365(4), γ=1.212(3), δ=4.318(1), and Δ=1.562(5) for H//ab, while α=−0.077(3), β=0.369(6), γ=1.338(1), δ=4.620(6), and Δ=1.689(2) for H//c. The universality principle allows the ΔSM(T,H) to be scaled onto a single universal curve independent of external field. The direction-dependent differing critical exponents imply anisotropic magnetic couplings in Cr3Te4, which reveal a magnetic interaction of the 3D-Ising type for H//ab while a 3D-XY one for H//c. This work is beneficial for understanding the intrinsic and anisotropic room-temperature ferromagnetism in CrxTey family.