A study on the kinetic arrest of magnetic phases in nanostructured Nd0.6Sr0.4MnO3 thin films

TL;DR

This study investigates how nanostructure morphology influences the kinetic arrest and phase coexistence in Nd0.6Sr0.4MnO3 thin films, revealing morphology-dependent magnetic glassy states and phase relaxation behaviors.

Contribution

It provides new insights into the morphology-driven changes in magnetic phase arrest and relaxation in manganite thin films using advanced magnetic protocols.

Findings

Rod morphology exhibits greater phase coexistence than granular.

Kinetic arrest extent varies with morphology and magnetic history.

Devitrification involves nucleation processes influenced by temperature.

Abstract

The Nd0.6Sr0.4MnO3 manganite system exhibits a phase transition from paramagnetic insulating (PMI) to ferromagnetic metallic (FMM) state around its Curie temperature TC = 270 K (bulk). The morphology-driven changes in the kinetically arrested magnetic phases in NSMO thin films with granular and a crossed-nano-rod-type morphology are studied. At low temperatures, the manganite thin films possess a magnetic glassy state arising from the coexistence of the high-temperature PMI phase and the low-temperature FMM phase. The extent of kinetic arrest and its relaxation was studied using the "cooling and heating in unequal field (CHUF)" protocol in magnetic and magneto-transport investigations. The sample with rod morphology showed a large extent of phase coexistence compared to the granular sample. Further, with a field-cooling protocol, time-evolution studies were carried out to understand the relaxation of arrested magnetic phases across these morphologically distinct thin films. The results on the devitrification of the arrested magnetic state are interpreted from the point of view of homogeneous and heterogeneous nucleation of the FM phase in the PM matrix with respect to temperature.