Non-equilibrium Magnetization Dynamics in the Fe_8 Single-Molecule Magnet Induced by High-Intensity Microwave Radiation

TL;DR

This paper investigates how high-intensity microwave radiation affects the magnetization of Fe_8 single-molecule magnets, revealing non-equilibrium dynamics and heating effects that alter spin state populations.

Contribution

It demonstrates the induction of non-equilibrium magnetization dynamics and heating effects in Fe_8 magnets using high-intensity microwave radiation, highlighting out-of-equilibrium behavior.

Findings

Resonant microwave radiation causes significant magnetization changes.

Transitions occur between excited states despite low thermal population.

Sample heating is observed at resonance, affecting spin states.

Abstract

Resonant microwave radiation applied to a single crystal of the molecular magnet Fe_8 induces dramatic changes in the sample's magnetization. Transitions between excited states are found even though at the nominal system temperature these levels have negligible population. We find evidence that the sample heats significantly when the resonance condition is met. In addition, heating is observed after a short pulse of intense radiation has been turned off, indicating that the spin system is out of equilibrium with the lattice.