| Original Articles |
|
|
|
|
Effectively Blocked Mechanism in Quantum Tunnelling of n-Coupled Single-Molecular Magnets |
| CHEN Zhi-De |
| Department of Physics, Jinan University, Guangzhou 510632 |
|
| Cite this article: |
|
CHEN Zhi-De 2005 Chin. Phys. Lett. 22 2663-2665 |
|
|
|
Abstract We present theoretical study on quantum tunnelling in n-coupled single-molecule magnets (SMMs) by spin-coherent-state path integral. It is found that, due to weak coupling between SMMs, the tunnelling process involving more than one-spin-flip is effectively blocked and the main contribution to the relaxation of the magnetization comes from the tunnelling processes involving just one-spin-flip. Starting from the negative saturated magnetization, the effect of the antiferromagnetic on tunnelling coupling is found to be qualitatively different from the ferromagnetic coupling. A criterion is developed to determine both the nature and the strength of the exchange coupling from the position of the first resonance of a spherical sample with homogeneous magnetization.
|
| Keywords:
75.45.+j
75.50.Xx
|
|
|
Published: 01 October 2005
|
|
| PACS: |
75.45.+j
|
(Macroscopic quantum phenomena in magnetic systems)
|
| |
75.50.Xx
|
(Molecular magnets)
|
|
|
|
|
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
