Electromagnetic Radiation Detection with Broad Spectral Sensitivity and Large Dynamic Range using Cantilever-based Photoacoustic Effect

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 analyse and optimise the measurement sensitivity using different dimensions of the cantilever which is one of the key components of the detection process. The numerical results are in good agreement with the experimentally obtained frequency response of the detection process. The power detection technique shows potential of finding future applications in the technologies that employ electromagnetic radiation detection for scientific studies and industrial purposes.