Quantum tunneling of two coupled single-molecular magnets

TL;DR

This paper investigates quantum tunneling phenomena in a dimer of two antiferromagnetically coupled single-molecule magnets, using numerical methods to understand tunneling behavior and hysteresis characteristics.

Contribution

It presents a detailed theoretical analysis of tunneling processes in a coupled molecular magnet dimer, including model parameter calculation and explanation of experimental observations.

Findings

No tunneling at zero magnetic field.

Sweep rate affects hysteresis step height.

Model accurately explains experimental data.

Abstract

Two single-molecule magnets are coupled antiferromagnetically to form a supramolecule dimer. We study the coupling effect and tunneling process by means of the numerical exact diagonalization method, and apply them to the recently synthesized supramoleculer dimer [Mn4]2 The model parameters are calculated for the dimer based on the tunneling process. The absence of tunneling at zero field and sweeping rate effect on the step height in the hysterisis loops are understood very well in this theory.