Spin-dependent thermoelectric properties of a magnetized zigzag graphene nanoribbon

Document Type : Original Article


School of Physics, Damghan University, Damghan, Iran


Spin caloritronics refers to generating spin current by thermal gradient. Spin caloritronics is an 
emerging new subfield of condensed matter physics concerned with coupled spin, charge, and energy 
transport in small structures and devices. In this paper, thermally induced spin transport in a 
magnetized zigzag graphene nanoribbon is explored. Using non-equilibrium Green’s function (NEGF) 
method in a tight-binding model, a temperature gradient applied between the left and right 
nonmagnetic electrodes, as thermal reservoirs in a magnetized zigzag graphene nanoribbon model 
junction so that the flowing of the up-spin and down-spin currents in the opposite directions can be 
induced which may be modulated by tuning of the back gate voltage. Furthermore, some 
thermoelectric properties of the junction, such as the spin-dependent Seebeck effect, electrical 
conductance, electron thermal conductance, and thermoelectric efficiency (ZT) of the model evaluated. 
Our calculations for the thermoelectric properties of the magnetized zigzag graphene nanoribbon 
indicate that for the zigzag edge graphene nanoribbon, the spin-dependent ZT is greater than the ZT of 
the electric charge. This means that for applications of spin thermal transport, the use of the zigzag 
edge graphene nanoribbons is appropriate.


Main Subjects

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