Effect of transverse anisotropy on the conductane in single molecule magnet Mn12

The transport through a single molecule magnet which is weakly coupled to the metallic leads is studied theoretically. We have employed the sequential tunneling approximation to calculate the current-voltage characteristics and the differential conductance. We have observed the negative differential conductance (NCD) in a range of parameters consistent with experimental ones. We have also studied the effect of a magnetic field for arbitrary angle with the easy axis of the molecule. The angle at which the differential current becomes zero defines the easy axis of molecule. Moreover, the magnetic field with arbitrary angle does not commute with the Hamiltonian of the molecule and leads to the mixing of zero-field eigenstates which gives a rich fine structure in the differential conductance. We have also observed the shift in coulomb blockade phenomenon in agreement with the experiments done on Mn12

Keywords:

single molecule magnet , coulomb blockade , negative differential conductance , complete current suppression