An infrared light detector, an infrared microscope, and an infrared spectrometer

摘要

PROBLEM TO BE SOLVED: To implement CSIP in which light of a plurality of wavelengths can be detected with high sensitivity by one detector.SOLUTION: In order to detect light (wavelengths: λ, λ, ..., λ) in (n) colors ((n) is an integer equal to or greater than 2) by a single detector, upper quantum wells for which a difference &Dgr;&egr; of energy levels (&egr;) between a basis subband (&egr;) and a first excitation subband is different are overlapped for (n) layers. Namely, a first electron layer is defined as a multiple quantum well layer. In the case of n=2, a first quantum well closer to an incidence plane side of incident infrared light and a second quantum layer well below the first quantum well are provided and a difference &Dgr;&egr;of energy levels between a basis subband and an excitation subband in the first quantum well and a difference &Dgr;&egr;of energy levels between a basis subband and an excitation subband in the second quantum well are designed to be &Dgr;&egr;&Dgr;&egr;. With this configuration, for example, light of a wavelength of 9 μm is detected by the first quantum well and light of a wavelength of 15 μm is detected by the second quantum well, such that light of a plurality of wavelengths can be detected with high sensitivity by one detector.