Analytical calculation of spin tunneling effect in single molecule magnet Fe8 with considering quadrupole excitation

Yousefi, Y; Fakhari, H; Muminov, K; Benam, M R

doi:10.29252/ijpr.17.5.743

Analytical calculation of spin tunneling effect in single molecule magnet Fe8 with considering quadrupole excitation

Authors

Y Yousefi

H Fakhari

K Muminov

M R Benam

https://doi.org/10.29252/ijpr.17.5.743

Abstract

Spin tunneling effect in Single Molecule Magnet Fe8 is studied by instanton calculation technique using SU(3) generalized spin coherent state in real parameter as a trial function. For this SMM, tunnel splitting arises due to the presence of a Berry like phase in action, which causes interference between tunneling trajectories (instantons). For this SMM, it is established that the use of quadrupole excitation (g dependence) changes not only the location of the quenching points, but also the number of these points. Also, these quenching points are the steps in hysteresis loops of this SMM. If dipole and quadrupole excitations in classical energy considered, the number of these steps equals to the number that obtained from experimental data.

Keywords

coherent state

spin tunneling

instanton

quadrupole excitation

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