Spin caloritronics in graphene

• The thermoelectric properties of a MQD attached to 2 single layer graphene sheets is considered.
• The quantum dot behaves as a spin filter.
• The spin-Seebeck coefficient dependence on the temperature and chemical potential is discussed.

Spin caloritronics, the combination of spintronics with thermoelectrics, based on spin and heat transport has attracted a great attention mainly in the development of low-power-consumption technology. In this work we study the thermoelectric properties of a quantum dot attached to two single layer graphene sheets as leads. The temperature difference on the two graphene leads induces a spin current which depends on the temperature and chemical potential. We demonstrate that the quantum dot behaves as a spin filter for selected values of the chemical potential and is able to filter electrons by their spin orientation. The spin thermopower has also been studied where the effects of the chemical potential, temperature and also the Coulomb repulsion due to the double occupancy of an energy level have been observed.