Low-Temperature Magnetization Relaxation in Magnetic Molecular Solids

TL;DR

This paper investigates how magnetization in magnetic molecular solids relaxes at low temperatures using Monte Carlo simulations, revealing a square-root time dependence consistent with experimental observations.

Contribution

It introduces a set of rate equations to analytically explain the square-root relaxation law observed in simulations and experiments.

Findings

Magnetization relaxes as a square-root of time at short times

Rate equations successfully describe the relaxation behavior

Simulation results align with experimental data

Abstract

The low temperature relaxation of the magnetization in magnetic molecular solids such as Fe$_8$ is studied using Monte Carlo simulations. A set of rate equations is developed to understand the simulations, and the results are compared. The simulations show that the magnetization of an initially saturated samples deviates as a square-root in time at short times, as observed experimentally, and this law is derived from the rate equations analytically.