Abstract: A new type of GaAs/GaAlAs quantum well infrared photodetectors based on a new physics mechanism was designed. Its calculation, manufacture,experiment mesurments and analysis were performed. Some new important characteristics are obtained, The calculated results are consistent with the experiments, which is better than results from the conventional GaAs/GaAlAs quantum well infrared photodetector. The simulation method of this new device about the current transport is given. The features of the large absorption band-width (5~10μm) and the low dark current are achieved.The device photo-electric response under the incident infrared radiation are observed for the first time. The choice of suitable operation bias is given preliminarily. It is estimated that the optical-induced signal will be increasing upon the increasing number of period.