Laser-lithographically written micron-wide superconducting nanowire single-photon detectors

TL;DR

This paper presents a method for fabricating micron-wide superconducting nanowire single-photon detectors on silicon using laser lithography, achieving high efficiency and sensitivity with larger wire widths.

Contribution

It introduces a laser lithography process for creating superconducting nanowire detectors with widths up to 1.43μm, enabling fast, large-area fabrication while maintaining high detection efficiency.

Findings

Achieved saturated internal detection efficiency with wire widths from 0.59μm to 1.43μm.

Demonstrated single-photon sensitivity in devices up to 4mm long.

Showed that laser lithography allows rapid structuring of large detector areas.

Abstract

We demonstrate the fabrication of micron-wide tungsten silicide superconducting nanowire single-photon detectors on a silicon substrate using laser lithography. We show saturated internal detection efficiencies with wire widths from 0.59$\mu$m to 1.43$\mu$m under illumination at 1550nm. We demonstrate both straight wires, as well as meandered structures. Single-photon sensitivity is shown in devices up to 4mm in length. Laser-lithographically written devices allow for fast and easy structuring of large areas while maintaining a saturated internal efficiency for wire width around 1$\mu$m.