PHOTORESPONSE OF A MINIATURIZED METAL-FILM BOLOMETER TO ULTRASHORT MIDINFRARED AND FAR-INFRARED LASER-PULSES

We report on an investigation of a photoresponse induced in a novel, m iniaturized low-noise metal resistor film bolometer when irradiated by ultrashort laser pulses (duration 100 ps to 200 ns) with wavelengths covering the mid- and far-infrared spectral ranges. Successful operati on at room temperature was achieved and almost constant detectivity wa s found over the whole frequency range investigated (15-1100 cm-1). Th e minimum detectable laser pulse energy was determined to be about 0.6 muJ (with an electronic bandwidth of 1 kHz). This high detectivity an d the miniaturized dimensions afford the possibility of building detec tor arrays applicable in mid- and far-infrared spectroscopy.