A high numerical aperture, polarization-insensitive metalens for long-wavelength infrared imaging

A type II indium arsenide / gallium antimonide (InAs-GaSb) strained layer superlattice (SLS) semiconductor is optimal for detecting long wavelength infrared (LWIR) signals for infrared imaging applications. However, as with all crystal structures dangling bonds at the surface of the semiconductor must be pacified with a passivant to maintain the integrity of the semiconductor. We report the most effective passivation layer for this III-V semiconductor by examining both the material and device characteristics of the devices pacified by silicon dioxide (SiO2), silicon nitride (SixNy), and zinc sulfide (ZnS). Our final reporting shows ZnS with a pre-passivation of ammonium sulfide ((NH4)2S) as being the most effective passivant.

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Quantum Dot Long-Wavelength Detectors

MRS Proceedings ◽

10.1557/proc-692-h3.2.1 ◽

2001 ◽

Vol 692 ◽

Author(s):

Pallab Bhattacharya ◽

Adrienne D. Stiff-Roberts ◽

Sanjay Krishna ◽

Steve Kennerly

Keyword(s):

Quantum Dots ◽

Quantum Dot ◽

Elevated Temperatures ◽

Infrared Imaging ◽

Normal Incidence ◽

Infrared Photodetectors ◽

Long Wavelength ◽

Quantum Dot Infrared Photodetectors ◽

Dark Currents ◽

Long Wavelength Infrared

AbstractLong-wavelength infrared detectors operating at elevated temperatures are critical for imaging applications. InAs/GaAs quantum dots are an important material for the design and fabrication of high-temperature infrared photodetectors. Quantum dot infrared photodetectors allow normal-incidence operation, in addition to low dark currents and multispectral response. The long intersubband relaxation time of electrons in quantum dots improves the responsivity of the detectors, contributing to better hightemperature performance. We have obtained extremely low dark currents (Idark = 1.7 pA, T = 100 K, Vbias = 0.1 V), high detectivities (D* = 2.9×108cmHz1/2/W, T = 100 K, Vbias = 0.2 V), and high operating temperatures (T = 150 K) for these quantum-dot detectors. These results, as well as infrared imaging with QDIPs, will be described and discussed.

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Long Wavelength Infrared Imaging under Ambient Thermal Radiation via All-Silicon Metalens

Optical Materials Express ◽

10.1364/ome.434362 ◽

2021 ◽

Author(s):

Arka Majumdar ◽

Luocheng Huang ◽

Zack Coppens ◽

Kent Hallman ◽

Zheyi Han ◽

...

Keyword(s):

Thermal Radiation ◽

Infrared Imaging ◽

Long Wavelength ◽

Long Wavelength Infrared

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Experimental demonstration of ghost imaging with speckled light in long-wavelength infrared range

Journal of Physics Conference Series ◽

10.1088/1742-6596/2091/1/012008 ◽

2021 ◽

Vol 2091 (1) ◽

pp. 012008

Author(s):

I Sh Khasanov

Keyword(s):

Infrared Imaging ◽

Optical Design ◽

Infrared Range ◽

Ghost Imaging ◽

Light Modulator ◽

Long Wavelength ◽

Thermal Cameras ◽

Infrared Frequency Range ◽

Long Wavelength Infrared ◽

Single Pixel

Abstract Infrared imaging with a single-pixel camera can achieve radiometric accuracy not currently available with multi-pixel thermal cameras. One of the actively investigated single-pixel camera technology is ghost imaging. We propose an optical design to experimentally demonstrate classical ghost imaging in the long-wave infrared frequency range with speckled light without using a spatial light modulator. We obtained an example low-quality ghost image and then used the cross-correlation function to identify and explain the main difficulties in ghost imaging with a thermal camera.

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