We report a high performance long-wavelength IR dual-band imager based on type-II superlattices with 100% cutoff wavelengths at 9:5 μm (blue channel) and 13 μm (red channel). Test pixels reveal background-limited behavior with specific detectivities as high as ∼5 × 1011 Jones at 7:9 μm in the blue channel and ∼1 × 1011 Jones at 10:2 μm in the red channel at 77 K. These performances were attributed to low dark currents thanks to the M-barrier and FabrÿCPerot enhanced quantum efficiencies despite using thin 2 μm absorbing regions. In the imager, the high signal-to-noise ratio contributed to median noise equivalent temperature differences of ∼20 milli-Kelvin for both channels with integration times on the order of 0.5 ms, making it suitable for high speed applications.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics