Magnetic Tunnel Window's Imprint and Beyond

TL;DR

This paper uses Monte Carlo simulations to study how magnetic dipoles relax via quantum tunneling, revealing the development of characteristic holes in field distributions related to the tunnel window and long-range order.

Contribution

It demonstrates the evolution of magnetic field distributions during relaxation, linking quantum tunneling effects to observable features like holes and long-range order signatures.

Findings

Holes form in field distributions matching the tunnel window shape

Long-range order signatures appear in distributions at low temperatures

Thermal energies influence the development of these features

Abstract

We report results from Monte Carlo simulations of systems of magnetic dipoles that relax through quantum tunneling, much as Fe_8 crystals at very low temperature.For short times, a hole develops in suitably defined magnetic field pseudo--distributions, which matches the shape of the tunnel window (TW). Much later, ordinary field distributions P(h) develop similar holes if thermal energies are not much larger than the TW's energy. Still later, below the long--range ordering (LRO) temperature, P(h) exhibits the signature of LRO.