Phenomenological model for the remanent magnetization of dilute quasi-one-dimensional antiferromagnets

TL;DR

This paper develops a phenomenological model to explain the remanent magnetization in dilute quasi-one-dimensional antiferromagnets, capturing the linear temperature dependence observed experimentally.

Contribution

It introduces a model based on uncompensated magnetic moments and their ferromagnetic correlation, providing a theoretical explanation for experimental remanent magnetization data.

Findings

Reproduces the linear temperature dependence of remanent magnetization

Uses a mean-field linear-chain approximation with realistic parameters

Explains the role of uncompensated moments in dilute antiferromagnets

Abstract

We present a phenomenological model for the remanent magnetization at low temperatures in the quasi-one-dimensional dilute antiferromagnets CH_{3}NH_{3}Mn_{1-x}Cd_{x} Cl_{3}\cdot 2H_{2}O and (CH_{3})_{2}NH_{2}Mn_{1-x}Cd_{x}Cl_{3}\cdot 2H_{2}O. The model assumes the existence of uncompensated magnetic moments induced in the odd-sized segments generated along the Mn(^{2+}) chains upon dilution. These moments are further assumed to correlate ferromagnetically after removal of a cooling field. Using a (mean-field) linear-chain approximation and reasonable set of model parameters, we are able to reproduce the approximate linear temperature dependence observed for the remanent magnetization in the real compounds.