Quantum Coherence in Fe8 Molecular Nanomagnets

TL;DR

This paper reports the observation of coherent quantum oscillations in Fe8 molecular nanomagnets, demonstrating quantum coherence effects in a spin-10 system through susceptibility measurements at very low temperatures.

Contribution

It provides experimental evidence of quantum coherence in Fe8 nanomagnets by directly observing quantum oscillations matching theoretical predictions.

Findings

Detection of two peaks in susceptibility corresponding to quantum splitting

Quantum oscillations observed at 680 MHz and 25 mK

Peak positions match theoretical predictions without fitting parameters

Abstract

We report observation of coherent quantum oscilations in spin-10 Fe8 molecular clusters. The powder of magnetically oriented Fe8 crystallites was placed inside a resonator, in a dc magnetic field perpendicular to the magnetization axis. The field dependence of the ac-susceptibility was measured up to 5 T, at 680 MHz, down to 25 mK. Two peaks in the imaginary part of the susceptibility have been detected, whose positions coincide, without any fitting parameters, with the predicted two peaks corresponding to the quantum splitting of the ground state in the magnetic field parallel and perpendicular to the hard magnetization axis.