Quantum grid infrared spectrometer

Abstract

We have designed and characterized an infrared spectrometer, which uses a linear array of quantum grid infrared photodetectors (QGIPs) as its spectral sensing elements. Each QGIP element shares the same detector material but has a different grid geometry. The detector material, which is based on a binary superlattice design, provides an 8–14 μm broadband absorption medium for the spectrometer. The geometry of the grid, which is the light coupling structure under normal incidence, selects individual absorption wavelength for each element. Using a linear array of QGIPs of different geometries, multiple wavelengths can be detected simultaneously, and the array thus forms a spectrometer. Multicolor infrared imaging can then be achieved by integrating such QGIPs in unit cells of a two-dimensional array.

Resonator-QWIPs and FPAs

“…In this case, the detector can be represented by a 2-dimensional geometry, and the 2-D modal transmission-line (MTL) method can provide an analytical solution. 6 Figure 2 compares the MTL solution and the present FEM solution for the same QGIP structure. The close agreement between the two methods confirms the validity of both approaches.…”

“…1(b) shows another structure, which is known as the quantum grid infrared photodetector (QGIP). 6 It consists of a linear array of grid lines of active materials, and the radiation is incident from the substrate side. In contrast to the collective resonance of the E-QWIP, the QGIP uses the metal layer on top of the grid as an optical antenna to receive and scatter the infrared radiation.…”

Electromagnetic modeling and resonant detectors and arrays

“…In Fig. 4, the EM model is shown to be able to account for various resonant effects including air cavity resonance [9], dipole antenna resonance [10], plasmonic resonance [11], and photonic crystal resonance [12]. And in Fig.…”

Designs and applications of corrugated QWIPs

“…(b) Bias dependence of peak responsivity R pk of the MW peaks at k p = 3.9 and 5.2 lm, and the LWIR peak at k p = 9.2 lm at T = 60 K. detector material, infrared detection can be performed at selective wavelengths. This approach offers more color detection than other approaches, requires only one indium contact per pixel, and only needs a standard single color readout circuit [19,20]. The coupling structure in our example is known as the quantum grid infrared photodetector (QGIP) [21].…”