Title :
Effect of electric field and temperature variability on spin dephasing in SiGe nanowires
Author :
Bishnoi, B. ; Chishti, S.S. ; Verma, A. ; Salimath, Arunkumar ; Ghosh, Bablu
Author_Institution :
Dept. of Electr. Eng., Indian Inst. of Technol. Kanpur, Kanpur, India
Abstract :
In this paper, we use semi classical Monte Carlo method to investigate Effect of electric field and temperature variability on spin polarized transport in SiGe nanowires (SiGeNWs) with Ge mole fraction of 0.2, 0.4, 0.6 and 0.8. We use a multi-subbands semi classical Monte Carlo approach to model spin dephasing. Monte Carlo simulations have been widely adopted to study electron transport in devices and have recently been used in conjunction with spin density matrix calculations to model spin transport. Spin dephasing in SiGe nanowires (SiGeNWs) is caused due to D´yakonov-Perel (DP) relaxation and due to Elliott-Yafet (EY) relaxation. The components of ensemble averaged spin variation have been studied for SiGe nanowires (SiGeNWs) along the nanowires length. The effect of variation of electric field and temperature on spin dephasing length has been studied. It is found that variation of the electric field does not affect spin dephasing length significantly but spin dephasing length decrease as Ge mole fraction increases from 0.2 to 0.8 for the same value of electric field in SiGe nanowires (SiGeNWs). The effect of variation of temperature is more visible and as temperature increases from 10K to 300K spin dephasing length decrease due to dominant increase of acoustic phonon scattering and it decrease more dominantly for higher value of Ge mole fraction such as 0.8 compare to 0.2.
Keywords :
Ge-Si alloys; Monte Carlo methods; electric field effects; nanowires; D´yakonov-Perel relaxation; Elliott-Yafet relaxation; SiGe; SiGe nanowire; acoustic phonon scattering; electric field effect; electron transport; mole fraction; multisubbands semiclassical Monte Carlo approach; spin density matrix calculation; spin dephasing; spin polarized transport; spin transport; temperature 10 K to 300 K; temperature variability; Electric fields; Monte Carlo methods; Nanowires; Phonons; Scattering; Silicon germanium; Vectors; Monte Carlo simulation; SiGe nanowires (SiGeNWs); spin dephasing length; spintranport;
Conference_Titel :
Electron Devices (CDE), 2013 Spanish Conference on
Conference_Location :
Valladolid
Print_ISBN :
978-1-4673-4666-5
Electronic_ISBN :
978-1-4673-4667-2
DOI :
10.1109/CDE.2013.6481373