Three-dimensional magnetic critical behavior in CrI$_3$

TL;DR

This study investigates the critical magnetic behavior of bulk CrI$_3$, revealing three-dimensional long-range magnetic interactions and providing critical exponents around the phase transition.

Contribution

It provides the first detailed critical exponents and analysis of bulk CrI$_3$, highlighting its 3D long-range magnetic coupling behavior.

Findings

Critical exponents $eta$=0.260(4), $ ext{T}_c$=60.05K

Long-range magnetic interactions with decay $J(r) \\approx r^{-4.69}$

Evidence of 3D magnetic critical behavior

Abstract

CrI$_3$ is a promising candidate for the van der Waals bonded ferromagnetic devices since its ferromagnetism can be maintained upon exfoliating of bulk crystals down to single layer. In this work we studied critical properties of bulk CrI$_3$ single crystals around the paramagnetic to ferromagnetic phase transition. Critical exponents $\beta$ = 0.260(4) with a critical temperature $T_c$ = 60.05(13) K and $\gamma$ = 1.136(6) with $T_c$ = 60.43(4) K are obtained by the Kouvel-Fisher method, whereas $\delta$ = 5.32(2) is obtained by a critical isotherm analysis at $T_c$ = 60 K. The critical exponents determined in bulk CrI$_3$ single crystals suggest a three-dimensional long-range magnetic coupling with the exchange distance decaying as $J(r)\approx r^{-4.69}$.