Room-Temperature Negative Differential Resistance and High Tunneling Current Density in GeSn Esaki Diodes.

Tunnel field-effect transistors (TFETs) are a promising candidate for low-power applications owing to their steep subthreshold swing of sub-60 mV per decade. For silicon- or germanium-based TFETs, the drive current is low due to the indirect band-to-band tunneling (BTBT) process. Direct-bandgap germanium-tin (GeSn) can boost the TFET performance since phonon participation is not required during the tunneling process.

Strain Effects on Rashba Spin-Orbit Coupling of 2D Hole Gases in GeSn/Ge Heterostructures.

A demonstration of 2D hole gases in GeSn/Ge heterostructures with a mobility as high as 20 000 cm V s is given. Both the Shubnikov-de Haas oscillations and integer quantum Hall effect are observed, indicating high sample quality. The Rashba spin-orbit coupling (SOC) is investigated via magneto-transport.