A5027401443- Neutrino Physics Research
- Photonic and Optical Devices
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Neural Networks and Reservoir Computing
- Optical Network Technologies
- Advanced Fiber Laser Technologies
- Particle Detector Development and Performance
- Advanced Photonic Communication Systems
- Astrophysics and Cosmic Phenomena
- Quantum, superfluid, helium dynamics
- Mechanical and Optical Resonators
- Laser-induced spectroscopy and plasma
- Photonic Crystals and Applications
- Semiconductor Lasers and Optical Devices
- Diamond and Carbon-based Materials Research
- Atmospheric Ozone and Climate
- Nuclear Physics and Applications
- Silicon Nanostructures and Photoluminescence
- Nuclear physics research studies
- Muon and positron interactions and applications
- Photocathodes and Microchannel Plates
- Advanced Optical Sensing Technologies
McGill University
2017-2023
Lawrence Livermore National Laboratory
2020-2023
Brookhaven National Laboratory
2021
University of Illinois Urbana-Champaign
2017-2019
University of British Columbia
2014-2016
McMaster University
2011-2013
University of Limerick
2012
Tennessee State University
2012
United States Naval Research Laboratory
1961
A search for neutrinoless double-beta decay ($0\nu\beta\beta$) in $^{136}$Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between $0\nu\beta\beta$ and background events. Relative previous analyses, signal detection efficiency has been raised from 80.8% 96.4$\pm$3.0% energy resolution of detector at Q-value improved $\sigma/E=1.23\%$ $1.15\pm0.02\%$ upgraded detector. Accounting new data, median 90% confidence level half-life sensitivity this analysis...
Results from a search for neutrinoless double-beta decay (0νββ) of ^{136}Xe are presented using the first year data taken with upgraded EXO-200 detector. Relative to previous searches by EXO-200, energy resolution detector has been improved σ/E=1.23%, electric field in drift region raised 50%, and system suppress radon volume between cryostat lead shielding implemented. In addition, analysis techniques that improve topological discrimination 0νββ background events have developed....
We demonstrate that n-doped resistive heaters in silicon waveguides show photoconductive effects with high responsivities. These heaters, integrated into microring resonator (MRR)-based filters, were used to automatically tune and stabilize the filter's resonance wavelength input laser's wavelength. This is achieved without requiring dedicated defect implantations, additional material depositions, photodetectors, or optical power tap-outs. Automatic stabilization of first-order MRR...
The next-generation Enriched Xenon Observatory (nEXO) is a proposed experiment to search for neutrinoless double beta ($0\nu\beta\beta$) decay in $^{136}$Xe with target half-life sensitivity of approximately $10^{28}$ years using $5\times10^3$ kg isotopically enriched liquid-xenon time projection chamber. This improvement two orders magnitude over current limits obtained by significant increase the mass, monolithic and homogeneous configuration active medium, multi-parameter measurements...
Abstract The nEXO neutrinoless double beta (0 νββ ) decay experiment is designed to use a time projection chamber and 5000 kg of isotopically enriched liquid xenon search for the in 136 Xe. Progress detector design, paired with higher fidelity its simulation an advanced data analysis, based on one used final results EXO-200, produce sensitivity prediction that exceeds half-life 10 28 years. Specifically, improvements have been made understanding production scintillation photons charge as...
The projected performance and detector configuration of nEXO are described in this pre-Conceptual Design Report (pCDR). is a tonne-scale neutrinoless double beta ($0νββ$) decay search $^{136}$Xe, based on the ultra-low background liquid xenon technology validated by EXO-200. With $\simeq$ 5000 kg enriched to 90% isotope 136, has half-life sensitivity approximately $10^{28}$ years. This represents an improvement about two orders magnitude with respect current results. Based experience gained...
We examine inter-channel and intra-channel crosstalk power penalties between non-return-to-zero on-off keying (NRZ-OOK) wavelength-division-multiplexing (WDM) channels for microring-based silicon photonic interconnects. first propose a new model that relates the penalty to interfering signals power, extinction ratio of non-return-to-zero, OOK modulated "victim" channel, finally bit-error-ratio is referenced to. As crosstalk, proposed agrees well with our recent experimental measurements....
We experimentally investigate the interchannel and intrachannel crosstalk of first- second-order microring resonator (MRR) filters fabricated on a silicon-on-insulator platform. find that there is an MRR radius maximizes wavelength division multiplexing channel count given waveguide geometry, maximum tolerable insertion loss, minimum permissible adjacent isolation. The measured power penalties due to two-channel demultiplexers based first-order series-coupled are presented as functions...
We apply deep neural networks (DNN) to data from the EXO-200 experiment. In studied cases, DNN is able reconstruct relevant parameters—total energy and position—directly raw digitized waveforms, with minimal exceptions. For first time, developed algorithms are evaluated on real detector calibration data. The accuracy of reconstruction either reaches or exceeds what was achieved by conventional approaches over course Most existing event classification in particle physics trained Monte Carlo...
Enabling cost-effective and power-efficient laser source on a silicon photonics (SiPh) platform is major goal that has been highly sought after. In the past two decades, tremendous effort made to develop various on-chip integration techniques enhance SiPh circuits with efficient light-emitting materials. Here we review our recent advancements in hybrid flip-chip of III-V lasers 300-mm monolithic platform. By leveraging advanced complementary metal oxide semiconductor (CMOS) manufacturing...
We demonstrate photonic ultra-efficient thermo-optic switches on a 220-nm silicon-on-insulator platform. used several approaches to increase the tuning efficiency of switches. folded waveguides in Michelson interferometer configuration optical interaction length light with heated region, and suspended structure improve thermal isolation. An ultra-low switching power 50 μW is realized an extinction ratio over 26 dB for transverse electric mode at 1550 nm. The 10%-90% response time switch 1.28...
Future tonne-scale liquefied noble gas detectors depend on efficient light detection in the VUV range. In past years Silicon Photomultipliers (SiPMs) have emerged as a valid alternative to standard photomultiplier tubes or large area avalanche photodiodes. The next generation double beta decay experiment, nEXO, with 5 tonne liquid xenon time projection chamber, will use SiPMs for detecting $178\,\text{nm}$ scintillation light, order achieve an energy resolution of $\sigma / Q_{\beta\beta} =...
Liquid xenon (LXe) is employed in a number of current and future detectors for rare event searches. We use the EXO-200 experimental data to measure absolute scintillation ionization yields generated by $\ensuremath{\gamma}$ interactions from $^{228}\mathrm{Th}$ (2615 keV), $^{226}\mathrm{Ra}$ (1764 $^{60}\mathrm{Co}$ (1332 keV 1173 keV) calibration sources, over range electric fields. The $W$ value that defines recombination-independent energy scale measured be...
We demonstrate, on the silicon-on-insulator platform, a modulator that uses quarter-wave phase-shifted Bragg grating resonator. The has open eye diagrams at data rates of up to 32 Gb/s. A bit error ratio less than 10- <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sup> is demonstrated using 2 xmlns:xlink="http://www.w3.org/1999/xlink">31</sup> - 1 pseudorandom binary sequence pattern rate 25
We analyze and demonstrate a method for increasing the efficiency of thermo-optic phase shifters on silicon-on-insulator platform. The lack cross-coupling between dissimilar waveguides allows highly dense waveguide routing under heating elements corresponding increase in efficiency. device with 9 10 µm wide heater achieve low switching power 95 µW, extinction ratio greater than 20 dB, less 0.1 dB ripple through spectrum footprint 800 × 180 µm. density is found not to negatively impact switch...
We present a search for electron-recoil signatures from the charged-current absorption of fermionic dark matter using EXO-200 detector. report an average background rate $6.8\ifmmode\times\else\texttimes\fi{}{10}^{4}\text{ }\text{ }\mathrm{cts}\text{ }{\mathrm{kg}}^{\ensuremath{-}1}\text{ }{\mathrm{yr}}^{\ensuremath{-}1}\text{ }{\mathrm{keV}}^{\ensuremath{-}1}$ above 4 MeV and find no statistically significant excess over our projection. Using total $^{136}\mathrm{Xe}$ exposure 234.1 kg yr,...
Journal Article Pentecostalism and Prosperity—The Socio-Economics of the Global Charismatic Movement Get access Movement. Edited by Katherine Attanasi Amos Yong. New York: Palgrave-Macmillan, 2012. 261pp. $90.00. Kyle Murray University LimerickLimerick, Ireland kyle.murray@ul.ie Search for other works this author on: Oxford Academic Google Scholar Church State, Volume 54, Issue 4, Autumn 2012, Pages 666–668, https://doi.org/10.1093/jcs/css100 Published: 18 October 2012
A search for Majoron-emitting modes of the neutrinoless double-beta decay $^{136}$Xe is performed with full EXO-200 dataset. This dataset consists a total exposure 234.1 kg$\cdot$yr, and includes data detector upgrades that have improved energy threshold relative to previous searches. lower limit T$_{1/2}^{\rm{^{136}Xe}}>$4.3$\cdot$10$^{24}$ yr at 90\% C.L. on half-life spectral index $n=1$ Majoron was obtained, factor 3.6 more stringent than from EXO-200, corresponding constraint...
We demonstrate photonic ultra-efficient thermo-optic switches on a 220-nm silicon-on-insulator platform. used several approaches to increase the tuning efficiency of switches. folded waveguides in Michelson interferometer configuration optical interaction length light with heated region, and suspended structure improve thermal isolation. An ultra-low switching power 50 μW is realized an extinction ratio over 26 dB for transverse electric mode at 1550 nm. The 10%–90% response time switch 1.28...
We demonstrate large-area silicon-on-insulator ring resonators with Q values of about 2×106 at critical coupling and 3.6×106 for heavily undercoupled conditions. A model has been developed to understand the impact waveguide backscattering subcomponent imperfections on spectral response our devices. The predicts appearance signals ports that would not have them under backscattering-free, ideal-power-splitting predictions are shown match phenomena observed in measurements.
We experimentally demonstrate an automated polarization receiver that couples light from any state output a single-mode fiber into the fundamental quasi-TE mode of waveguide in integrated silicon photonic circuit.
Understanding reflective properties of materials and photodetection efficiency (PDE) photodetectors is important for optimizing energy resolution sensitivity the next generation neutrinoless double beta decay, direct detection dark matter, neutrino oscillation experiments that will use noble liquid gases, such as nEXO, DARWIN, DarkSide-20k, DUNE . Little information currently available about reflectivity PDE in because measurements are difficult to conduct a cryogenic environment at short...
The resonant defect-enhanced photodiode has received recent attention for its potential use in silicon photonic applications such as wavelength division multiplexing (WDM). Here, we analyze the nature of enhancement micro-ring photodiodes by exploring roles defect content and ring geometry. Through post-processing to gradually reduce concentration, demonstrate an optimized peak responsivity 160 mA W−1 a resonator having linewidth 0.12 ± 0.01 nm 12.8 ± 0.9 dB extinction. We also show that is...