Quantum Phase Interference and Neel-Vector Tunneling in Antiferromagnetic Molecular Wheels
arXiv:0902.4564 · doi:10.1103/PhysRevLett.102.157202
Abstract
The antiferromagnetic molecular wheel Fe18 of eighteen exchange-coupled Fe(III) ions has been studied by measurements of the magnetic torque, the magnetization, and the inelastic neutron scattering spectra. The combined data show that the low-temperature magnetism of Fe18 is very accurately described by the Neel-vector tunneling (NVT) scenario, as unfolded by semiclassical theory. In addition, the magnetic torque as a function of applied field exhibits oscillations that reflect the oscillations in the NVT tunnel splitting with field due to quantum phase interference.
5 pages, 4 figures, REVTEX4, to appear in PRL