2008/10/31 by Tae-Suk Kim, Choong‐Ki Lee, Kim, Tae-Suk +7
Materials Science · Physics and Astronomy · #Carbon Nanotubes in Composites #FOS: Physical sciences #Graphene research and applications #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.0810.5719
openalex publication_date 2008/10/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report on our theoretical study of the magnetoresistance in spin polarized transport through a finite carbon nanotube (CNT). Varying the Fermi energy of a CNT and the relative strength of couplings to two ferromagnetic (FM) electrodes, we studied the conductance as well as the magnetoresistance (MR). Due to resonant transport through discrete energy levels in a finite CNT, the conductance and MR are oscillating as a function of the CNT Fermi energy. The MR is peaked at the conductance valleys and dipped close to the conductance peaks. When couplings to two FM electrodes are asymmetric, the MR dips become negative under a rather strong asymmetry. When couplings are more or less symmetric, the MR dips remain positive except for a very strong coupling case. Under strong coupling case, the line broadening is significant and transport channels through neighboring energy levels in a CNT interfere with each other, leading to the negative MR.