Patent ID: 6979825

Claim:
A spectrometer comprising: (1) quantum-grid infrared photodetector (QGIP) elements each adapted to detect energy at a particular range of wavelengths, the QGIP elements each being further adapted to generate a photocurrent, each photocurrent being proportional to the detected energy at the particular range of wavelengths, the particular range of wavelengths forming a continuous spectrum of wavelengths, each QGIP element comprising: (A) a semiconductor substrate having a planar surface, the semiconductor substrate being transparent; (B) a lower contact layer located on the semiconductor substrate; (C) quantum-well infrared photodetector (QWIP) elements optically coupled to the semiconductor substrate, each QWIP element operating as a waveguide such that incident light is directed through the QWIP element, each QWIP element further operating as a resonator such that scattered light resonates within the QWIP element, each QWIP element comprising: (1) a plurality of superlattices, each superlattice being adapted to detect absorption peaks, each absorption peak being defined by one of the particular ranges of wavelengths within the continuous spectrum of wavelengths, each superlattice comprising: (a) a plurality of binary quantum wells coupled together by inter-well barriers adapted to permit energy transfer between the binary quantum wells, each of the binary quantum wells being adapted to detect energy transition characterized by one of the detected absorption peaks; (D) an upper contact layer located on the QWIP elements; and (E) a metallic layer located on the upper contact layer.