Critical behavior near magnetic transition in room-temperature kagome magnet Fe3Sn2

Abstract

Fe 3 Sn 2 is a promising kagome magnet known for holding room-temperature topologically stable spin textures and exhibiting non-trivial momentum-space topology. In this work, we present field-dependent ac susceptibility measurements revealing a dip-like anomaly persisting upto ∼600 K in Fe3Sn2 single crystal, indicative of topologically stable skyrmionic excitation in the system. Additionally, a comprehensive analysis of the critical behavior near the ferromagnetic to paramagnetic phase transition was performed to estimate the critical exponents β, γ, and δ. The values are determined using multiple methods, including the modified Arrott plot, Kouvel–Fisher method, and critical isotherm analysis. The obtained values are mutually consistent and satisfy Widom’s scaling relation, confirming their reliability. Moreover, they obey the renormalized scaling hypothesis, showing a clear bifurcation in the scaling plot for T>Tc and T<Tc, reaffirming that the critical exponents are intrinsic to the system. The extracted critical exponents indicate that the spins are coupled via short-range interaction and the critical behavior of Fe3Sn2 is governed by the 3D Heisenberg exchange interactions, which decay as J∼d−4.962.