1. Effect of phase transition on quantum transport in group-IV two-dimensional U-shape device.
- Author
-
Sadi, Mohammad Abdullah, Gupta, Gaurav, and Liang, Gengchiau
- Subjects
PHASE transitions ,QUANTUM transitions ,SPIN Hall effect ,GREEN'S functions ,ELECTRIC fields - Abstract
The effect of phase-transition from the quantum-spin-hall to the band-insulator phase on the transport through a three-terminal U-shape spin-separator has been computationally investigated via non-equilibrium green function formalism. Two-dimensional group-IV elements have been comprehensively appraised as the device material. The device separates the unpolarized current injected at the source-terminal into nearly 100% spin-polarized currents of the opposite polarities at the two drain terminals. The phase-transition activated by the electric-field orthogonal to the device is shown to extensively influence the current magnitude and its spin-polarization, and the effect is stronger for materials with smaller intrinsic spin-orbit coupling. Moreover, the device length and the area under field are shown to critically affect the device characteristics on phase change. It is shown that the same device can be operated as a spin-filter by inducing phase-transition selectively in the channel. The results are important for designing spin-devices from Group-IV monolayers. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF