Wide frequency band radiation detector

An original planar n-GaAs diode with n-n(+) junction has been constructed to detect radiation in the range from millimetre to micrometer wavelength, The operational principle of this detector is based on free carrier heating in semiconductor by incident power. The analytical formulae for the voltage arising in the planar diode under microwave and laser radiation obtained by solving phenomenological carrier transport and Poisson equations shows no frequency dependence of the detected voltage up to 1 millimetre wavelength. The frequency dependence of detected voltage in high frequency range results from the frequency dependence of the momentum relaxation time of hot carriers Experimental results of microwave and laser radiation measurements have shown a good agreement with theoretical suggestions.