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We present a digital system for measurement of neutron spectra in mixed gamma-neutron fields. The signal from a standard scintillation detector is sampled at rate up to 1 GHz, using 12-bit analog-to-digital converters. First stage of the signal processing is performed on a Virtex 6 FPGA and partial results are streamed through a fast Ethernet link to a computer, where the final processing takes place...
Current technology used for monitoring fetal well-being has been ineffective at reducing rates of harm to the fetus during the intrapartum period, yet its adoption has significantly increased the number of emergency C-sections performed. Transabdominal fetal pulse oximetry (TFO) aims to reduce the number of surgical interventions through non-invasive measurements of fetal oxygen saturation. When developing...
Terahertz (THz) waves, which represent the frequency region between radio and light waves from 0.1 THz to 10 THz, have attracted considerable attention in the interdisciplinary field of electronics and photonics. Their unique potential applications, such as in ultra-broadband wireless communication, spectroscopic sensing, and non-destructive imaging, are now being developed [1]. However, most existing...
There has been significant advancement in photonic infrared (IR) detector technology in the past decade. In this tutorial, I will cover the basics of photonic IR detectors including the detection mechanisms and figures of merit. I will end with a survey of a few current technologies. Infrared imaging (3–25μm) has been an important technological tool for the past 60 years since the first report of...
We study an entangled QKD system using photons at 780nm, 1550nm and 4μm from a SPDC nonlinear crystal, over a 30km maritime channel. An analysis of the channel at each wavelength is performed and the QKD system is simulated for each wavelength.
HBT effect of thermal light between different modes based on multi-mode interference is directly observed in a modified Michelson interferometer with orthogonal polarizations by a two-photon absorption detector at ultrashort timescale, which serves as a new unique tool for ultrafast quantum bunching distribution.
A honeycomb photodetector architecture is proposed for low-cost CMOS-compatible blue-enhanced sensing applications. In this paper, a physical model is developed to characterize the responsivity of honeycomb photodetectors. The model is then used to determine the optimum honeycomb physical dimensions for maximum responsivity and quantum efficiency. To implement the model in a real application, a test...
This paper proposes a SPAD array sensor based on breakdown pixel extraction architecture with background readout for scintillation detectors. The proposed architecture extracts the addresses of only the breakdown pixels during the exposure time of the next frame. Therefore, this sensor minimizes the dead time and improve the readout efficiency. A SPAD array sensor was fabricated in a 0.18 μm CMOS...
Compton Scatter Imaging is a promising approach in imaging science. Since it employs scattered radiation that is otherwise rejected, it is claimed to improve the sensitivity of current radiation-based imaging systems. The Radon transform on V-lines models a Compton Camera and its inversion through filtered back-projection leads to an efficient way to reconstruct the density of a radiotracer. Recently,...
A solid state 3D scanner based on a pulsed laser diode source and narrow time gating of a 2D CMOS single photon avalanche diode (SPAD) detector array is presented. The imager uses an on-chip delay-locked loop to program the time gating of 40 sub-arrays individually. The prototype detector has 80 × 25 pixels with a fill factor of 32 % in the sensor area. The chip has been fabricated in a 0.35 μm high-voltage...
Silicon photomultiplier (SiPM) detectors are emerging semiconductor devices addressing the challenge of low-light detection for single-photon counting contexts. High-performance SiPM front-end electronics requires availability of reliable electrical models. Many accurate SiPM models have matured in recent years; nevertheless, circuit parameter extraction is fairly burdensome and involves extensive...
In this paper we present an algorithm of signal processing that allows the use of a PC-based oscilloscope in order to count events with a time stamping register. This novel application has a direct use on recording of arrival times of individual photons detected on one or more detection channels in quantum optics experiments. In particular, we report experimental results of the time stamping acquisition...
We present an x-ray quanta image sensor (XQIS) utilizing temporal oversampling and CMOS image sensor technology. The output of the XQIS is a binary bit frame with each bit representing the presence or absence of a detected x-ray photon. The bit frames are read out at very high rate (>1000fps) and a series or bit values are combined to form pixel values using digital frame integration. A system...
The advancement and use of silicon photo multiplier (SiPM) technology has enabled portable devices for applications such as scintillation detection to be developed. The proposed analogue to digital converter (ADC) architecture and field programmable gate array (FPGA) system configuration advances on analogue signal processing methods, traditionally employed for gamma isotope identification applications...
The characteristics of quantum channel play important roles on designing a high performance quantum communication system. In this paper, we analyze the fidelity of polarization state travelling through a non-Markovian optical fiber depolarizing quantum channel with color noise environment. The quantum bit error rate (QBER) of a polarization coding BB84 quantum key distribution (QKD) system under non-Markovian...
We report on the design, fabrication and electro-optical characterization at T = 2.9 K of a photon number resolving detector designed to obtain a pulse-position resolution. This pulse-position-resolving detector (PPRD) is based on the spatial multiplexing of four superconducting nanowire avalanche photodiodes (SNAPs) [8, 9] connected in series. We choose to exploit the 2-SNAP configuration (i.e.,...
We present a single photon counting measurement setup and characterize a Single Photon Counting Module (SPCM) by determining the measurement result for photon detection probability and linearity. The measurements were made by using calibrated photodetectors and calibrated attenuators, and are traceable to the cryogenic radiometer-based primary standard. A detailed measurement uncertainty analysis...
Spectral computed tomography (SCT) makes use of the spectral dependence of X-ray attenuation in tissues and contrast agents to separate the attenuation data into more than two energy bins. Current SCT detectors are costly and the measured data have low signal to noise ratio due to the detector's narrow bin bandwidth and quantum noise. A new approach called coded aperture compressive X-ray SCT that...
Photonic-electronic integration is a key technology to master data traffic growth and therefore an enabler of future network technologies. For some time now, a novel silicon-based photonic-electronic integration technology, photonic BiCMOS, is under development at IHP. Photonic BiCMOS is a planar technology co-integrating monolithically on a single substrate high-speed RF frontend electronics - by...
A source of entangled photons is connected via optical fibers to two single photon detectors. By simultaneously measuring pump power dependencies of the detection probabilities at each detector, as well as the probability of coincidence counts, we reliably extract all relevant system parameters.
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