Magnetocrystalline Anisotropy and Magnetocaloric Effect Studies on the Room-temperature 2D Ferromagnetic Cr$_4$Te$_5$

Abstract

We present a thorough study on the magnetoanisotropic properties and magnetocaloric effect in the layered ferromagnetic Cr 4 Te 5 single crystals by performing the critical behaviour analysis of magnetization isotherms. The critical exponents β =0.485(3), γ=1.202(5), and δ =3.52(3) with a Curie temperature of T C ≈ 340.73(4) K are determined by the modified Arrott plots. We observe a large magnetocrystalline anisotropy K u =330 kJ/m 3 at 3 K which gradually decreases with increasing temperature. Maximum entropy change -∆S max M and the relative cooling power (RCP) are found to be 2.77 J/kg -K and 88.29 J/kg, respectively near T C when the magnetic field applied parallel to ab-plane. Rescaled -∆S M (T, H) data measured at various temperatures and fields collapse into a single universal curve, confirming the second order magnetic transition in this system. Following the renormalization group theory analysis, we find that the spin-coupling is of 3D Heisenberg-type, {d : n} = {3 : 3}, with long-range exchange interactions decaying as J(r) = r -(d+σ ) = r -4.71 .