Quantum Fluctuations in Large-Spin Molecules

TL;DR

This paper predicts a novel quantum effect in large-spin molecules with easy-axis anisotropy, showing a susceptibility peak due to quantum fluctuations, which is experimentally accessible and influenced by the multi-spin structure.

Contribution

It introduces a new quantum fluctuation-induced susceptibility peak in large-spin molecules, emphasizing the importance of multi-spin effects for accurate description.

Findings

Susceptibility exhibits a quantum-origin peak under perpendicular external field.

The effect is observable with current experimental techniques.

Multi-spin nature of Mn12 is crucial for the quantum peak.

Abstract

A new type of mesoscopic quantum effect in large-spin molecules possessing easy-axis anisotropy, such as Mn12, is predicted. The response of such a system to an external field applied perpendicular to the easy axis is considered. It is shown that the susceptibility of this system exhibits a peculiar peak of purely quantum origin. This effect arises from very general properties of quantum fluctuations in spin systems. We demonstrate that the effect is entirely accessible for contemporary experimental techniques. Our studies show that the many-spin nature of the Mn12 clusters is important for a correct description of this quantum peak.