Variation of T$_g$ with magnetic field in a magnetic glass

Archana Lakhani; Pallavi Kushwaha; R. Rawat; Kranti Kumar; A. Banerjee; P. Chaddah

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arXiv · 0904.2635

Variation of T$_g$ with magnetic field in a magnetic glass

Archana Lakhani·Pallavi Kushwaha·R. Rawat·Kranti Kumar·A. Banerjee·P. Chaddah

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Abstract

Glass-like arrest has recently been reported in various magnetic materials. As in structural glasses, the kinetics of a first-order transformation is arrested while retaining the higher-entropy phase as a non-ergodic state. We show visual mesoscopic evidence of the irreversible devitrification of the arrested antiferromagnetic-insulating phase in $Pr_{0.5}Ca_{0.5}Mn_{0.975}Al_{0.025}O_3$ to its equilibrium ferromagnetic-metallic phase with isothermal increase of magnetic field, similar to its iso-field devitrification on warming. The slope of $T_g$ vs magnetic field in half-doped manganites is shown to have a sign governed by Le Chatelier's Principle.

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Archana Lakhani, Pallavi Kushwaha, R. Rawat, Kranti Kumar, A. Banerjee, P. Chaddah. 2009-04-17. Variation of T$_g$ with magnetic field in a magnetic glass. https://arxiv.org/abs/0904.2635

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