Optical power detector with broad spectral coverage, high detectivity and large dynamic range

TL;DR

This paper introduces a versatile optical power detector utilizing the photoacoustic effect, capable of broad spectral coverage from ultraviolet to far infrared, with high detectivity and a large dynamic range, suitable for various light-based technologies.

Contribution

The paper presents a novel photoacoustic-based optical power detector with unprecedented spectral coverage, high linear dynamic range, and potential extension into terahertz frequencies.

Findings

Spectral coverage from ultraviolet to far infrared.

Dynamic range of 80 dB, from 6 nW to 600 mW.

Potential for extension to terahertz region.

Abstract

Optical power measurements are needed in practically all technologies based on light. Here we report a general-purpose optical power detector based on the photoacoustic effect. Optical power incident on the detector's black absorber produces an acoustic signal, which is further converted into an electrical signal using a silicon-cantilever pressure transducer. We demonstrate an exceptionally large spectral coverage from ultraviolet to far infrared, with the possibility for further extension to the terahertz region. The linear dynamic range of the detector reaches 80 dB, ranging from a noise-equivalent power of 6 nW to 600 mW.