Theoretical Studies of Tunnel Magnetoresistance and Shot Noise in a Schottky-Barrier Carbon Nanotube Transistor with Ferromagnetic Contacts

摘要

A Schottky-barrier carbon nanotube field-effect transistor with ferromagnetic contacts was modelled. The theoretical method combines a tight-binding model and the non-equilibrium Green function technique. Tunnel magnetoresistance as well as current noise of the carbon nanotube field-effect transistor are the main issues addressed in this study. It is shown that the former may exceed 50%, whereas the latter is characterized by the Poissonian Fano factor (F) within the sub-threshold region, and the sub-Poissonian F ≈ 0.5 for elevated gate voltages. Remarkably, reorientation of relative magnetization alignments of the contacts may lead to noticeable changes in the current noise.