Monte Carlo Simulations of Spin Transport in Nanoscale InGaAs Field Effect Transistors

Spin-based logic devices could operate at very high speed with very low energy consumption and hold significant promise for quantum information processing and metrology. Here, an in-house developed, experimentally verified, ensemble self-consistent Monte Carlo device simulator with a Bloch equation model using a spin-orbit interaction Hamiltonian accounting for Dresselhaus and Rashba couplings is developed and applied to a spin field effect transistor (spinFET) operating under externally applied voltages on a gate and a drain. In particular, we simulate electron spin transport in a 25nm gate length In0.7Ga0.3As metal-oxide-semiconductor field-effect transistor (MOSFET) with a CMOS compatible architecture. We observe non-uniform decay of the net magnetization between the source and gate and a magnetization recovery effect due to spin refocusing induced by a high electric field between the gate and drain. We demonstrate coherent control of the polarization vector of the drain current via the source-drain and gate voltages, and show that the magnetization of the drain current is strain-sensitive and can be increased twofold by strain induced into the channel.

Figure: Dresselhaus Hamiltonian vectors (in units of meV) of 4 electron ensembles corresponding to thin slices along the channel for a single Monte Carlo run (VG = 0.9V, VD = 0.5V) orange (far left) x=-55nm, RichBlue (centre-left) x=-20nm, Cyan (centre right) x=0nm, Forest Green (far right) x=27nm. Grey arrow show the scale whilst Red arrows show the average.	Video: 3D model of In0.3Ga0.7As MOSFET device showing spin polarisation of electrons, injected with s_x polarisation, along n-channel with 4% strain in the [001] direction (Red) and unstrained (Purple). Created with our finite-element quantum-corrected ensemble Monte Carlo simulator with electron spins in a realistic nanoscale III-V field effect transistor model to investigate spin effects within a realistic semiconductor device. The Monte Carlo simulator has in particular been augmented to consider Dresselhaus and Rashba effects.
	Music: Ghostpocalypse - 8 Epilog Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 License, http://creativecommons.org/licenses/by/3.0/

Citation

B. Thorpe, K. Kalna, F.C. Langbein, S.G. Schirmer. Monte Carlo Simulations of Spin Transport in Nanoscale InGaAs Field Effect Transistors. J Applied Physics, 122, 223903, 2017. [DOI:10.1063/1.4994148] [arXiv:1610.04114] [PDF]

License

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in "B. Thorpe, K. Kalna, F.C. Langbein, S.G. Schirmer. Monte Carlo Simulations of Spin Transport in Nanoscale InGaAs Field Effect Transistors. J Applied Physics, 122, 223903, 2017" and may be found at DOI:10.1063/1.4994148.