  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.
