Contactless photoconductivity measurements on (Si) nanowires

TL;DR

This paper introduces a contactless method using a superconducting resonator to measure photoconductivity in silicon nanowires, revealing their large dielectric polarizability and enabling studies of electron transport coupling.

Contribution

It presents a novel contactless measurement technique for nanowires using microwave resonators, expanding the understanding of their transport and dielectric properties.

Findings

Nanowires show large dielectric polarizability unlike bulk silicon.

The technique is applicable to various semiconducting nanowires and molecules.

It enables investigation of electron transport coupling to surface acoustic waves.

Abstract

Conducting nanowires possess remarkable physical properties unattainable in bulk materials. However our understanding of their transport properties is limited by the difficulty of connecting them electrically. In this Letter we investigate phototransport in both bulk silicon and silicon nanowires using a superconducting multimode resonator operating at frequencies between 0.3 and 3 GHz. We find that whereas the bulk Si response is mainly dissipative, the nanowires exhibit a large dielectric polarizability. This technique is contactless and can be applied to many other semiconducting nanowires and molecules. Our approach also allows to investigate the coupling of electron transport to surface acoustic waves in bulk Si and to electro-mechanical resonances in the nanowires.