Martensite-like transition and spin-glass behavior in nanocrystalline Pr0.5Ca0.5MnO3

TL;DR

This study investigates the magnetic phase transitions and spin-glass behavior in 10 nm Pr0.5Ca0.5MnO3 nanoparticles, revealing a Martensite-like transition and reduced saturation fields compared to bulk material.

Contribution

It provides new insights into size-dependent magnetic transitions and spin-glass phenomena in nanocrystalline manganites, highlighting a Martensite-like transition and magnetic disorder.

Findings

Saturation field reduced to ~250 kOe in nanoparticles

Exponential decay of critical magnetic field with temperature

Presence of spin-glass-like phase indicated by AC susceptibility

Abstract

We report on isothermal pulsed (20 ms) field magnetization, temperature dependent AC - susceptibility, and the static low magnetic field measurements carried out on 10 nm sized Pr0.5Ca0.5MnO3 nanoparticles (PCMO10). The saturation field for the magnetization of PCMO10 (~ 250 kOe) is found to be reduced in comparison with that of bulk PCMO (~300 kOe). With increasing temperature, the critical magnetic field required to 'melt' the residual charge-ordered phase decays exponentially while the field transition range broadens, which is indicative of a Martensite-like transition. The AC - susceptibility data indicate the presence of a frequency-dependent freezing temperature, satisfying the conventional Vogel-Fulcher and power laws, pointing to the existence of a spin-glass-like disordered magnetic phase. The present results lead to a better understanding of manganite physics and might prove helpful for practical applications.