Critical behavior of Griffiths ferromagnets

TL;DR

This paper develops new scaling relations for Griffiths ferromagnets based on the distribution of Yang-Lee zeroes and confirms these predictions with experimental data on specific materials.

Contribution

It introduces novel scaling relations near the Griffiths transition derived from the distribution of Yang-Lee zeroes, supported by experimental validation.

Findings

Predicted a discontinuity on the analogue of the critical isotherm.

Experimental data for La0.7Ca0.3MnO3 support the Griffiths ferromagnet model.

New scaling relations are consistent with observed magnetization and heat capacity.

Abstract

From a heuristic calculation of the leading order essential singularity in the distribution of Yang-Lee zeroes, we obtain new scaling relations near the ferromagnetic-Griffiths transition, including the prediction of a discontinuity on the analogue of the critical isotherm. We show that experimental data for the magnetization and heat capacity of $\mathrm{La_{0.7}Ca_{0.3}MnO_3}$ are consistent with these predictions, thus supporting its identification as a Griffiths ferromagnet.