A Landau-Zener multi-crossing method has been used to investigate the tunnel splittings in high quality Mn12-acetate single crystals in the pure quantum relaxation regime and for fields applied parallel to the magnetic easy axis. With this method several individual tunneling resonances have been studied over a broad range of time scales. The relaxation is found to be non-exponential and a distribution of tunnel splittings is inferred from the data. The distributions suggest that the inhomogeneity in the tunneling rates is due to disorder that produces a non-zero mean value of the average transverse anisotropy, such as in a solvent disorder model. Further, the effect of intermolecular dipolar interaction on the magnetic relaxation has been studied.
Cite
@article{arxiv.cond-mat/0209167,
title = {Tunneling Splittings in Mn12-Acetate Single Crystals},
author = {E. del Barco and A. D. Kent and E. M. Rumberger and D. N. Hendrickson and G. Christou},
journal= {arXiv preprint arXiv:cond-mat/0209167},
year = {2009}
}
Comments
Europhysics Letters (in press). 7 pages, including 3 figures