Shortwave Infrared InGaAs Detectors On-Chip Integrated with Subwavelength Polarization Gratings.

Shortwave infrared polarization imaging can increase the contrast of the target to the background to improve the detection system's recognition ability. The division of focal plane polarization indium gallium arsenide (InGaAs) focal plane array (FPA) detector is the ideal choice due to the advantages of compact structure, real-time imaging, and high stability. However, because of the mismatch between nanostructures and photosensitive pixels as well as the crosstalk among the different polarization directions, the currently reported extinction ratio (ER) of superpixel-polarization-integrated detectors cannot meet the needs of high-quality imaging.

Design and Fabrication of Broadband InGaAs Detectors Integrated with Nanostructures.

A visible-extended shortwave infrared indium gallium arsenide (InGaAs) focal plane array (FPA) detector is the ideal choice for reducing the size, weight and power (SWaP) of infrared imaging systems, especially in low-light night vision and other fields that require simultaneous visible and near-infrared light detection. However, the lower quantum efficiency in the visible band has limited the extensive application of the visible-extended InGaAs FPA. Recently, a novel optical metasurface has been considered a solution for a high-performance semiconductor photoelectric device due to its highly controllable property of electromagnetic wave manipulation.

Broadband high quantum efficiency InGaAs/InP focal plane arrays via high precision plasma thinning.

We report on the fabrication of a 160×120 visible (Vis)-extended InGaAs/InP focal plane array (FPA) by means of the inductively coupled plasma etching. Compared to the conventional Vis-InGaAs FPAs, higher quantum efficiency in the Vis spectrum has been achieved. High precision thinning of the -type InP contact layer down to 10 nm has led to quantum efficiencies higher than 60% over a broad wavelength range of 500-1700 nm.

Design and fabrication of an InGaAs focal plane array integrated with linear-array polarization grating.

Polarization imaging plays a crucial role in modern photonic applications such as remote sensing, material classification, and reconnaissance. A novel InGaAs focal plane array integrated with linear-array polarization grating is proposed and fabricated to meet the practical needs of near-infrared polarization imaging. In order to accurately evaluate the polarization performance of a fabricated detector, the improved test system is used to measure the transmittance and extinction ratio (ER).

Research on polarization performance of InGaAs focal plane array integrated with superpixel-structured subwavelength grating.

Polarization imaging has become a widely-applied detection technique, due to the capabilities of enhanced image contrast and object recognition. Here, we demonstrate 320 × 256 InGaAs focal plane array (FPA) integrated with superpixel-structured subwavelength aluminum grating. An extinction ratio of up to 19:1 at 1310 nm is realized, which indicates a good capability of near-infrared polarization detection.

IGA-rule 17 for performance estimation of wavelength-extended InGaAs photodetectors: validity and limitations.

A rule of thumb, denoted as IGA-rule 17, has been developed to describe the temperature and cutoff wavelength-dependent dark currents of wavelength-extended InGaAs photodetectors in a 2-3 μm band. The validity and limitations of the rule are discussed. This rule is intended as an index for device developers to evaluate their technologies in processing, a simple tool for device users to estimate reachable performance at various conditions in their design, and an effective bridge between the two.

Electron-initiated low noise 1064 nm InGaAsP/InAlAs avalanche photodetectors.

We report an electron-initiated 1064 nm InGaAsP avalanche photodetectors (APDs) with an InAlAs multiplier. By utilizing a tailored digital alloy superlattice grading structure, a charge layer and a p type InAlAs multiplier, an unity gain quantum efficiency of 48%, a low room temperature dark current of 470 pA at 90% breakdown voltage, and a low multiplication noise with an effective k ratio of ∼0.2 are achieved.

Subwavelength Gold Grating as Polarizers Integrated with InP-Based InGaAs Sensors.

There are currently growing needs for polarimetric imaging in infrared wavelengths for broad applications in bioscience, communications and agriculture, etc. Subwavelength metallic gratings are capable of separating transverse magnetic (TM) mode from transverse electric (TE) mode to form polarized light, offering a reliable approach for the detection in polarization way. This work aims to design and fabricate subwavelength gold gratings as polarizers for InP-based InGaAs sensors in 1.

Scale effects of low-dimensional relaxor ferroelectric single crystals and their application in novel pyroelectric infrared detectors.

Scaling effects of low-dimensional relaxor ferroelectric single crystals have induced large delocalization of domain switching, leading to a dramatic increase in pyro-electric performances by 2-5.5 times, and promoting the detectivity of fabricated pyroelectric detectors to an international leading level of 2.21 × 10(9) cmHz(1/2) /W at 10 Hz, 4 times higher than that of commercial LiTaO3 -based detectors.

An organic solvent-free microwave-assisted extraction of some priority pollutants of phenols in lake sediments.

Alkaline water was used for the microwave-assisted extraction of some priority pollutants of phenols in sediments, i.e. phenol (Ph), 2-chlorophenol (2CP), 2,4-dichlorophenol (2,4DCP), 4-chlorophenol (4CP), 4-dinitrophenol (4NP) and pentachlorophenol (PCP).