Ballistic quantum transport through Ge/Si core/shell nanowires

TL;DR

This paper investigates ballistic hole transport in Ge/Si core/shell nanowires, revealing interference patterns, conductance quantization, and large g-factors, which are crucial for quantum device development.

Contribution

It provides the first detailed analysis of ballistic transport and quantum interference effects in Ge/Si core/shell nanowires at low temperatures.

Findings

Observation of Fabry-Pérot interference patterns

Conductance plateaus at integer multiples of 2e^2/h

Large effective Landé g-factors in nanowires

Abstract

We study ballistic hole transport through Ge/Si core/shell nanowires at low temperatures. We observe Fabry-P$\acute{e}$rot interference patterns as well as conductance plateaus at integer multiples of 2e$^2$/h at zero magnetic field. Magnetic field evolution of these plateaus reveals large effective Land$\acute{e}$ g-factors. Ballistic effects are observed in nanowires with silicon shell thicknesses of 1 - 3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic subband-resolved transport.