Electromagnetic radiation detection using cantilever-based photoacoustic effect: A method for realizing power detectors with broad spectral sensitivity and large dynamic range

• Published in: Sensors and actuators. A. Physical. Vol. 337; p. 113191
• Main Authors: Sharma, Sucheta, Laurila, Toni, Rossi, Jussi, Uotila, Juho, Vainio, Markku, Manoocheri, Farshid, Ikonen, Erkki
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 16-04-2022; Elsevier BV
• Subjects: Cantilever pressure sensor; Detectors; Dynamic range; Elastic waves; Electromagnetic radiation; Electromagnetics; Industrial applications; Mathematical models; Measurement; Numerical models; Optical metrology; Photoacoustic; Photoacoustic effect; Photoacoustic numerical model; Power measurement; Radiation; Radiation detection; Radiation effects; Sensitivity analysis; Sensors; Soot; Spectral sensitivity; Photoacoustic; Cantilever pressure sensor; Soot; Detectors; Radiation detection; Photoacoustic numerical model; Optical metrology
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2021.113191

•This paper presents a detector of electromagnetic radiation power using cantilever-based photoacoustic effect.•A numerical model has been developed to identify the optimum criteria for effective detector performance.•The experimental results are in good agreement with the presented numerical model.•Good detection sensitivity and spectral coverage from 325 to 1523 nm, have been achieved.•A linear dynamic range of around six orders of magnitude has been obtained with this technique.
Schematic representation of the PA radiation detection system. The system consists of three subsystems to convert input radiation to heat by using CS (candle soot) absorber target, to produce mechanical response with the cantilever and, finally, to generate the PA signal from interferometric readout. There are two main gas domains: primary gas cell which directly heats up when the connected CS absorbs radiation and the balance chamber along with two capillaries that reduces the acceleration noise in the system. a. Velocity diagram of gaseous medium within the PA cell. The arrows represent how the induced pressure interacts with the cantilever to generate mechanical response. b. Cantileer being displaced due to the generated pressure within the PA cell. The highest displacement zone is concentrated at the tip of the cantilever. [Display omitted]
A sensitive photoacoustic detection approach employing a silicon cantilever is investigated for power measurement of electromagnetic radiation. The technique which is actuated by pressure waves generated through radiation-induced heat depicts high sensitivity for a considerably large spectral range from 325 nm to 1523 nm. The implemented method shows linear response in the measurement of radiation power from 15 nW to 6 mW demonstrating a dynamic range of almost six orders of magnitude. A numerical model has been developed to analyze and optimize the measurement sensitivity. The model allows studying different dimensions of the cantilever which is one of the key components of the radiation detection process. The numerical results are in good agreement with experimental results. The electromagnetic power detection technique shows future potential for industrial applications and scientific studies.