Spin thermoelectric effects in Resonant Tunnelling Diodes
Hernández Nicolau, Javier (Supervisor Sánchez, David)
Master Thesis (2013)
We consider thermoelectric effects in quantum conductors within the scattering approach. In particular, we study the thermoelectric conductance and Seebeck coefficient of a Resonant Tunneling Diode (RTD). We obtain a maximum thermopower of the order of kB/e which shows a conduction of carriers from the hot to the cold reservoir. The maximum can be modiffed with the position of the energy level in the quantum
well E0 and with the temperature. In the second part of this Master thesis, a spin splitting in the level is included. We find a splitting in the thermopower maximum and the possibility to obtain completely polarized spin currents by modifying the system parameters. Finally, we study the spin thermopower due to the generation of spin biases in response to thermal gradients. Our results show two peaks in the spin
thermopower of different sign. This effect involves a spin polarized current for spin-up or spin-down electrons even in the absence of charge current. We discuss optimal values of this effect as a function of temperature.