Continuous focal plane array for detection of terahertz radiation

Doping of the lead telluride and related alloys with the group III impurities results in appearance of unique physical features of a material, such as persistent photoresponse, enhanced responsive quantum efficiency (up to 100 photoelectrons/incident photon), radiation hardness and many others. As a result, single photodetectors based on Pb1-xSnxTe(In) demonstrate extremely high performance in the Terahertz wavelength range. Furthermore, it is shown that local long-lived non-equilibrium states are generated in Pb1-xSnxTe(In) alloys at low temperatures under the action of local Terahertz excitation. This result opens a possibility for construction of a "continuous" focal-plane array for detection of Terahertz radiation. Ideas for readout of information from this array are discussed.