Photo-Induced Thermo-Spin In Ferromagnetic Graphene Field Effect Transistor
Thermospin effects in ferromagnetic graphene mesoscopic device are investigated. The thermo-spin characteristics such as spin Seebeck coefficient, the thermal conductance, and spin figure of merit are expressed in terms of the tunneling probability of Dirac fermions for both parallel and antiparallel spin alignments of electrons. This tunneling probability and the corresponding electrical conductance are derived by solving Dirac equation for both spin alignments. Numerical calculations are performed and the obtained results show that the values of Seebeck coefficient, thermal conductance, and figure of merit are different for spin up and spin down. Their values are increased as the frequency of the induced ac-field increases, that is, the thermospin transport through such device is enhanced by the photon energy. The present research is very important in the field of spin caloritronics on the nanoscale systems.
Ferromagnetic Graphene, Spin Caloritronics, Thermospin Seebeck Coefficient, Thermal Conductance, Figure of Merit and Ac-Field
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