<title>Design and operation of self-biased high-gain amplifier arrays for photon-counting sensors</title>

We have shown the design and fabrication of a microfluidic flow cytometer. The microfluidic flow cytometer has been used to characterize microspheres of different sizes. The device is consisted of a microchannel, electronics, and integrated optics. The microchannel has three inlets. Two inlets are used to introduce sheath flows and one middle inlet is assigned as sample inlet. The sample flow is hydrodynamically focused at the center of the microchannel by two side streams (sheath flows). Also arrays of four chevron grooves compress the sample flow from the top and bottom of the microchannel. The core flow contains microspheres at a certain concentration. Detection of the microspheres at the interrogation region of the channel is performed by integrated optics and electronics. The scattered light emitted from the microspheres is collected by a multi-plex photo diode (MPPC). The results are recorded using data acquisition (DAQ) unit. The MPPCs employed in the setup is the new generation of photon counter devices with an excellent detection limit, a compact size, and capability of recording data at high gain compared to previous generation of photodetectors such as photomultipliers or avalanche photon diodes. The flow cytometer was sensitive enough to collect data from 3 μm microspheres using such mentioned sensitive photon counting unit. We have also used COMSOL Multiphysics software to investigate velocity and pressure distribution as well as concentration distribution along the microchannel. The average voltage collected by MPPC was 1.9 V for 10.2 μm and 1.6 V for 3.2 μm microsphere.

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COMPARATIVE TEST OF TWO METHODS OF QUANTUM EFFICIENCY ABSOLUTE MEASUREMENT BASED ON SQUEEZED VACUUM DIRECT DETECTION

International Journal of Quantum Information ◽

10.1142/s0219749911007265 ◽

2011 ◽

Vol 09 (supp01) ◽

pp. 251-262 ◽

Cited By ~ 3

Author(s):

I. N. AGAFONOV ◽

M. V. CHEKHOVA ◽

A. N. PENIN ◽

G. O. RYTIKOV ◽

O. A. SHUMILKINA ◽

...

Keyword(s):

Quantum Efficiency ◽

Direct Detection ◽

Photon Counting ◽

Absolute Measurement ◽

High Gain ◽

New Method ◽

Absolute Calibration ◽

Squeezed Vacuum ◽

The Difference ◽

Absolute Quantum

We realize and test in experiment a method recently proposed for measuring absolute quantum efficiency of analog photodetectors. Similar to the traditional (Klyshko) method of absolute calibration, the new one is based on the direct detection of two-mode squeezed vacuum at the output of a traveling wave OPA. However, in the new method, one measures the difference-photocurrent variance rather than the correlation function of photocurrents (number of coincidences), which makes the technique applicable for high-gain OPA. In this work we test the new method versus the traditional one for the case of photon-counting detectors where both techniques are valid.

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Engineering sensitivity and spectral range of photodetection in van der Waals materials and hybrids

Nano Express ◽

10.1088/2632-959x/ac46b9 ◽

2021 ◽

Author(s):

Shaili Sett ◽

Aparna Parappurath ◽

Navkiranjot Kaur Gill ◽

Neha Chauhan ◽

Arindam Ghosh

Keyword(s):

Van Der Waals ◽

Photon Counting ◽

High Sensitivity ◽

High Gain ◽

Physical Mechanisms ◽

Temperature Detection ◽

Recent Developments ◽

High Bandwidth ◽

Industrial Standards ◽

Very High

Abstract Exploration of van der Waals heterostructures in the field of optoelectronics has produced photodetectors with very high bandwidth as well as ultra-high sensitivity. Appropriate engineering of these heterostructures allows us to exploit multiple light-to-electricity conversion mechanisms, ranging from photovoltaic, photoconductive to photogating processes. These mechanisms manifest in different sensitivity and speed of photoresponse. In addition, integrating graphene-based hybrid structures with photonic platforms provides a high gain-bandwidth product, with bandwidths >> 1 GHz. In this review, we discuss the progression in the field of photodetection in 2D hybrids. We emphasize the physical mechanisms at play in diverse architectures and discuss the origin of enhanced photoresponse in hybrids. Recent developments in 2D photodetectors based on room temperature detection, photon-counting ability, integration with Si and other pressing issues, that need to be addressed for these materials to be integrated with industrial standards have been discussed.

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Structure Design and Simulation of a Pulsar Navigation-Oriented X-Ray Detector

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.1428 ◽

2013 ◽

Vol 834-836 ◽

pp. 1428-1431

Author(s):

Lian Sheng Liu ◽

Jun Zhang ◽

Jian Wu Chen ◽

Fu Chang Zuo ◽

Zhi Wu Mei

Keyword(s):

Photon Counting ◽

High Gain ◽

Structure Design ◽

Static Structure ◽

X Ray ◽

Voltage Drops ◽

Avalanche Photo Diode ◽

Diode Detector ◽

Output Capacitance ◽

Pulsar Navigation

Based on the advantages silicon drift detector (SDD) and avalanche photo diode (APD), a droplet-like avalanche drift diode detector (DADD) is proposed. Firstly, the overall structure of the DADD has been designed considering the parameters of bow-shaped curves, distance of drift ring, extra biased voltage and width of drift ring. Secondly, the surface potential of DADD has been simulated and obtained the relation of dark current of drift ring and voltage drops between different drift rings. In addition, static structure analysis and steady state thermal analysis have been implemented. The simulation results show that, the DADD has a good structure and features with high gain, smaller output capacitance and high photon counting capacity, which is appropriate for the pulsar navigation system.

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Effect of energy filtering on micro-diffraction in the SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017075x ◽

1994 ◽

Vol 52 ◽

pp. 604-605

Author(s):

James F. Mancuso ◽

Leo A. Fama ◽

William B. Maxwell ◽

Jerry L. Lehman ◽

Hasso Weiland ◽

...

Keyword(s):

Detection Efficiency ◽

Ccd Camera ◽

High Gain ◽

Microchannel Plate ◽

Electrostatic Energy ◽

Energy Filtering ◽

Electron Channelling ◽

Low Energy Electrons ◽

Low Sensitivity ◽

Angular Field Of View

Micro-diffraction based crystallography is essential to the design and development of many classes of ‘crafted materials’. Although the scanning electron microscope can provide crystallographic information with high spatial resolution, its current utility is severely limited by the low sensitivity of existing diffraction techniques (ref: Dingley). Previously, Joy showed that energy filtering increased contrast and pattern visibility in electron channelling. This present paper discribes the effect of energy filtering on EBSP sensitivity and backscattered SEM imaging.The EBSP detector consisted of an electron energy filter, a microchannel plate detector, a phosphor screen, optical coupler, and a slow scan CCD camera. The electrostatic energy filter used in this experiment was constructed as a cone with 5 coaxial electrodes. The angular field-of-view of the filter was approximately 38°. The microchannel plate, which was the initial sensing component, had high gain and had 50% to 80% detection efficiency for the low energy electrons that passed through the retarding field filter.

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Equivalent Noise Dose Obtained Through Hearing Aids in the Classrooms of Hearing-Impaired Children

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.2103.147 ◽

1990 ◽

Vol 21 (3) ◽

pp. 147-150

Author(s):

Ronald A. Wilde

Keyword(s):

Hearing Aids ◽

High Gain ◽

Hearing Impaired ◽

Deaf Children ◽

Impaired Children ◽

Very High ◽

Hearing Impaired Children

A commercial noise dose meter was used to estimate the equivalent noise dose received through high-gain hearing aids worn in a school for deaf children. There were no significant differences among nominal SSPL settings and all SSPL settings produced very high equivalent noise doses, although these are within the parameters of previous projections.

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