title: Interference in spin tunnelling of small magnetic particles.
abstract: A previously studied (Enz and Schilling 1986  J. Phys. C: Solid State Phys.  19 1765) magnetocrystalline anisotropic Hamiltonian with a magnetic field applied along the medium axis is reconsidered, with emphasis on the topological phase effect. A quantum inteference effect is revealed.
authors.affiliation: Institute of Physics, Academia Sinica, PO Box 603-99, Beijing 100080, People's Republic of China. Institute of Theoretical Physics, Shanxi University, Taiyuan 030006, People's Republic of China.
authors.forename: X B
authors.initials: XB
authors.lastname: Wang
authors.forename: F C
authors.initials: FC
authors.lastname: Pu