Manifestation of intermediate spin for Fe$_{8}$

TL;DR

This paper reports the first clear observation of intermediate spin phenomena in Fe$_{8}$ magnetic clusters, demonstrating periodic tunnel splitting oscillations linked to the system's parity, influenced by magnetic fields.

Contribution

It provides experimental evidence and a detailed theoretical explanation of intermediate spin effects in mesoscopic magnetic particles, bridging concepts from anyon theory to magnetic molecular systems.

Findings

Periodic tunnel splitting oscillations observed in Fe$_{8}$

Intermediate spin effects linked to magnetic field orientation

Theoretical model explaining parity-dependent phenomena

Abstract

Intermediate spin, which occurs in the theory of anyons, can also be exhibited by mesoscopic magnetic particles. The necessary broken time reversal symmetry is due to a suitably directed magnetic field. As a function of this field a system passes periodically through points which correspond to whole or half-integer spin. Intermediate spin is defined by fields which lie between these points. Since the tunnel splitting in the ground doublet vanishes for half-integer spin, this splitting becomes periodic. The doubly periodic oscillations observed in the magnetic molecular cluster Fe$_{8}$ represent the first unequivocal observation of this phenomena. Here the whole or half-integer nature of the system, i.e., the parity, is periodic for a field which is along either the easy or hard axis or a suitable combination of the two. A detailed theory is presented.