Three-dimensional Ising Ferrimagnetism of Cr-Fe-Cr trimers in FeCr2Te4

TL;DR

This study investigates the critical magnetic behavior of FeCr2Te4, revealing a three-dimensional Ising ferrimagnetic transition driven by long-range interactions among Cr-Fe-Cr trimers, with critical exponents close to theoretical models.

Contribution

It provides the first detailed critical behavior analysis of FeCr2Te4, linking its ferrimagnetism to 3D Ising universality and long-range spin interactions.

Findings

Critical exponents close to 3D Ising model

Long-range interactions decay as r^{-4.88}

Ferrimagnetism driven by itinerant ferromagnetism among Cr-Fe-Cr trimers

Abstract

We carried out a comprehensive study of magnetic critical behavior in single crystals of ternary chalcogenide FeCr$_2$Te$_4$ that undergoes a ferrimagnetic transition below $T_c$ $\sim$ 123 K. Detailed critical behavior analysis and scaled magnetic entropy change indicate a second-order ferrimagentic transition. Critical exponents $\beta = 0.30(1)$ with $T_c = 122.4(5)$ K, $\gamma = 1.22(1)$ with $T_c = 122.8(1)$ K, and $\delta = 4.24(2)$ at $T_c$ $\sim$ 123 K suggest that the spins approach three-dimensional Ising ($\beta$ = 0.325, $\gamma$ = 1.24, and $\delta$ = 4.82) model coupled with the attractive long-range interactions between spins that decay as $J(r)\approx r^{-4.88}$. Our results suggest that the ferrimagnetism in FeCr$_2$Te$_4$ is due to itinerant ferromagnetism among the antiferromagnetically coupled Cr-Fe-Cr trimers.