In-vacuum scattered light reduction with cupric oxide surfaces for sensitive fluorescence detection

TL;DR

This paper presents a simple, cost-effective method to produce ultra-high vacuum compatible, low-reflectivity cupric oxide surfaces that enhance sensitive fluorescence detection by reducing scattered light.

Contribution

The authors introduce a rapid, chemical growth process for black CuO surfaces on copper, suitable for complex geometries and high-temperature baking, improving optical blackness for fluorescence detection.

Findings

CuO surfaces have reflectivity comparable to commercial black coatings.

The method is rapid, low-cost, and compatible with ultra-high vacuum conditions.

Application improves sensitivity in laser-induced fluorescence detection.

Abstract

We demonstrate a simple and easy method for producing low-reflectivity surfaces that are ultra-high vacuum compatible, may be baked to high temperatures, and are easily applied even on complex surface geometries. Black cupric oxide (CuO) surfaces are chemically grown in minutes on any copper surface, allowing for low-cost, rapid prototyping and production. The reflective properties are measured to be comparable to commercially available products for creating optically black surfaces. We describe a vacuum apparatus which uses multiple blackened copper surfaces for sensitive, low-background detection of molecules using laser-induced fluorescence.