Rewritable nanoscale oxide photodetector

TL;DR

This paper introduces rewritable nanoscale photodetectors at LaAlO3/SrTiO3 interfaces, enabling high-gain, gate-tunable detection of visible to near-infrared light, with potential for integrated optoelectronic systems.

Contribution

It demonstrates a reversible AFM writing technique to create nanoscale photodetectors with high gain and tunability on a single materials platform.

Findings

Nanoscale photodetectors with 2-3 nm junctions created via AFM writing.

Devices exhibit high photoconductive gain and gate-tunability.

Potential for integration with nanowires and transistors in optoelectronic applications.

Abstract

Nanophotonic devices seek to generate, guide, and/or detect light using structures whose nanoscale dimensions are closely tied to their functionality. Semiconducting nanowires, grown with tailored optoelectronic properties, have been successfully placed into devices for a variety of applications. However, the integration of photonic nanostructures with electronic circuitry has always been one of the most challenging aspects of device development. Here we report the development of rewritable nanoscale photodetectors created at the interface between LaAlO3 and SrTiO3. Nanowire junctions with characteristic dimensions 2-3 nm are created using a reversible AFM writing technique. These nanoscale devices exhibit a remarkably high gain for their size, in part because of the large electric fields produced in the gap region. The photoconductive response is gate-tunable and spans the visible-to-near-infrared regime. The ability to integrate rewritable nanoscale photodetectors with nanowires and transistors in a single materials platform foreshadows new families of integrated optoelectronic devices and applications.