Emergence of exchange bias in van der Waals magnetic alloy CrxPt1−xTe

Van der Waals magnetic alloys are able to use alloy concentration to introduce desirable properties for applications. CrxPt1₋xTe2 is a recently developed magnetic alloy noted for its stability in ambient conditions. We study the effects of the alternating Cr concentration in CrxPt1−xTe2 (x ≥ 0.4) by measuring and comparing the hysteresis of x = 0.35 and x = 0.45. We observe the emergence of an exchange bias effect in Cr0.45Pt0.55Te2, without typical exchange bias sources such as an adjacent antiferromagnetic. We perform Monte Carlo simulations utilizing parameters from first-principles calculations that recreate the exchange bias in hysteresis loops of Cr0.45Pt0.55Te2. From our simulations, we infer the source of our exchange bias to be magnetic moments locked into free energy minima that resist macroscopic symmetric magnetization reversal. This work presents multiple ways to introduce desirable magnetic properties to van der Waals magnets.