Generation and detection of high-speed pulses of mid-infrared radiation with intersubband semiconductor lasers and detectors

Semiconductor lasers and detectors based on intersubband electron transitio ns are used to generate and measure high-speed pulses of mid-infrared radia tion. In particular, we use a commercial comb generator to gain-switch a st ate-of-the-art 8-mu m quantum cascade laser mounted in a high-speed package , The output pulses of this device are then detected with a small-area quan tum-well infrared photodetector, also packaged for high-speed operation. Pu lse widths shorter than 90 ps are directly measured with this system. Accou nting for the finite response time of the detection electronics, a deconvol ved duration of approximately 45 ps is extrapolated.