Path dependent resistivity study across field induced paramagnetic to ferromagnetic transition in Se doped CoS$_2$

TL;DR

This study investigates the resistivity behavior and magnetic transitions in Se-doped CoS2, revealing a field-dependent transition with giant magnetoresistance and evidence of kinetic arrest in a disordered to ordered magnetic phase change.

Contribution

It provides the first evidence of kinetic arrest in a disordered to ordered first order magnetic transition, expanding understanding of glass-like magnetic states.

Findings

Giant positive magnetoresistance of about 160% at 5 K.

Non-monotonic variation of critical field with temperature.

Reentrant transition observed under CHUF protocol.

Abstract

A systematic study of thermomagnetic irreversibility CoS$_{1.76}$Se$_{0.24}$ has been carried out. Our study shows that the resistivity at low temperature can be tuned by cooling in different magnetic fields and the critical field required for paramagnetic (PM) to ferromagnetic (FM) transition varies non-monotonically with temperature. The field induced PM to FM transition results in giant positive magnetoresistance (MR) of about 160\% at 5 K. Measurements under CHUF (cooling and heating in unequal magnetic field) protocol show reentrant transition on warming under higher magnetic field (than that applied during cooling). It indicates that the glass like behaviour in this system can be explained in the framework of the kinetic arrest of first order transition. Among the growing list of diverse system showing glass like arrested magnetic states, the present system is the first example where, kinetic arrest is observed for a disordered (here PM) to ordered (here FM) first order transition.