Growth of PbTe nanowires by Molecular Beam Epitaxy

TL;DR

This paper reports the successful growth of defect-free PbTe nanowires via molecular beam epitaxy, demonstrating their potential for quantum devices through observed ballistic transport and quantum interference effects.

Contribution

It introduces a method to fabricate high-quality PbTe nanowires suitable for quantum applications, which was not previously demonstrated.

Findings

Achieved defect-free single crystalline PbTe nanowires with high aspect ratios.

Demonstrated bipolar transport and extracted the bandgap from nanowire devices.

Observed Fabry-Perot oscillations indicating quasiballistic conductance.

Abstract

Advances in quantum technology may come from the discovery of new materials systems that improve the performance or allow for new functionality in electronic devices. Lead telluride (PbTe) is a member of the group IV-VI materials family that has significant untapped potential for exploration. Due to its high electron mobility, strong spin-orbit coupling and ultrahigh dielectric constant it can host few-electron quantum dots and ballistic quantum wires with opportunities for control of electron spins and other quantum degrees of freedom. Here, we report the fabrication of PbTe nanowires by molecular beam epitaxy. We achieve defect-free single crystalline PbTe with large aspect ratios up to 50 suitable for quantum devices. Furthermore, by fabricating a single nanowire field effect transistor, we attain bipolar transport, extract the bandgap and observe Fabry-Perot oscillations of conductance, a signature of quasiballistic transmission.