A5089760753- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- High-pressure geophysics and materials
- Quantum and electron transport phenomena
- Superconducting and THz Device Technology
- Superconducting Materials and Applications
- Spacecraft and Cryogenic Technologies
- Electron Spin Resonance Studies
- Physics of Superconductivity and Magnetism
- Visual perception and processing mechanisms
- Microwave Engineering and Waveguides
- Orbital Angular Momentum in Optics
- Photorefractive and Nonlinear Optics
- Semiconductor Quantum Structures and Devices
- Advanced Materials Characterization Techniques
- Cold Atom Physics and Bose-Einstein Condensates
- Molecular Junctions and Nanostructures
- Advancements in Semiconductor Devices and Circuit Design
- Hydraulic and Pneumatic Systems
- Radio Frequency Integrated Circuit Design
- Advanced Antenna and Metasurface Technologies
- Force Microscopy Techniques and Applications
- Perovskite Materials and Applications
- Quantum Computing Algorithms and Architecture
University of Waterloo
2013-2020
Hyosung Corporation (South Korea)
2018
Samsung (South Korea)
2018
Perimeter Institute
2014-2018
Canadian Institute for Advanced Research
2018
Leiden University
2006-2014
Huygens Institute for History and Culture of the Netherlands
2014
To enable atomic-scale observations of model catalysts under conditions approaching those used by the chemical industry, we have developed a second generation, high-pressure, high-temperature scanning tunneling microscope (STM): ReactorSTM. It consists compact STM scanner, which tip extends into 0.5 ml reactor flow-cell, that is housed in ultra-high vacuum (UHV) system. The can be operated from UHV to 6 bars and room temperature up 600 K. A gas mixing analysis system optimized for fast...
Spin-orbit coupling of light has come to the fore in nanooptics and plasmonics, is a key ingredient topological photonics chiral quantum optics. We demonstrate basic tool for incorporating analogous effects into neutron optics: generation detection beams with coupled spin orbital angular momentum. The 3He filters are used conjunction specifically oriented triangular coils prepare lattices spin-orbit correlations, as demonstrated by their spin-dependent intensity profiles. These correlations...
We predict and experimentally verify an entoptic phenomenon through which humans are able to perceive discriminate structured light with space-varying polarization. Direct perception discrimination is possible the observation of distinct profiles induced by interaction between polarization gradients in a uniform-intensity beam radially symmetric dichroic elements that centered on foveola macula human eye. A psychophysical study was conducted where optical states coupled orbital angular...
A novel design of an array half-wave superconductive microstrip resonators is described. The resonator intended to be useful for electron spin resonance studies thin film samples at cryogenic temperatures. It achieves a high quality factor, has small mode-volume, and creates uniform magnetic field in plane above the resonator. device made Niobium on sapphire wafer tested with static field. Variation Q-factor versus field's strength different temperatures reported good agreement simulation...
We describe an experimental protocol to characterize magnetic field dependent microwave losses in superconducting niobium microstrip resonators. Our approach provides a unified view that covers two well-known loss mechanisms: quasiparticle generation and vortex motion. find is the dominant mechanism for parallel fields. For perpendicular fields, motion or switches from motion, depending on cooling procedures. In particular, we introduce plot of quality factor versus resonance frequency as...
A superconducting three-pole Chebyshev band-pass filter is designed, fabricated and tested to be used in microwave set-up Cryogenic refrigerator. The design based on the reflected group delay method it implemented interdigital configuration a coplanar waveguide with Niobium (Nb) over Sapphire dielectric. response circuit model (lumped element, J-inverter coupling matrix synthesis), full wave simulation of its physical realization s-parameter measurement are compared. With proper packaging...
We find that annealing a previously chemically etched interferometer at 800 °C dramatically increased the interference fringe visibility from 23% to 90%. The Bragg plane misalignments were also measured before and after using neutron rocking curves, showing alignment was improved across annealing. This suggests current interferometers with low may be salvageable become an important step in fabrication process of future interferometers, leading less need for chemical etching larger more...
Neutrons are a powerful probe in material science with unique penetrating abilities. A major challenge stems from the fact that neutron optical devices limited to refractive indices on order of n≈1±10−5. By exploiting advances precision manufacturing, we designed and constructed micro-meter period triangular grating high-aspect ratio 14.3. The manufacturing quality is demonstrated white-light interferometric data microscope imaging. Neutron-scattering experiment results presented, showing...
Recently, micro-resonator structures have demonstrated considerable enhancement of ESR spectroscopy. The high-quality factor and confined mode these resonators (cavities) lead to an enhanced spin-cavity interaction that both increase sensitivity for conventional measurements allow access experiments can investigate utilize effects associated with strongly interacting spin ensembles cavities. Superconducting micro-resonators are particularly interesting due their natural compatibility low...
Neutron interferometry at the National Institute of Standards and Technology is a well-established program that performs experiments in wide range areas including materials science, quantum information, precision measurements coherent incoherent scattering lengths, dark energy/fifth force searches. Central to continued success this further understanding elimination instabilities coherence-losses whether they are from thermal, vibrational, or dynamical sources. We have spent considerable...
The construction is described of a monolithic thick-crystal perfect silicon neutron interferometer using an ultra-high-precision grinding technique and combination annealing chemical etching that differs from the prior interferometers. second to have been annealed after machining first be etching. Monitoring interference signal at each post-fabrication step provides measurement subsurface damage its alleviation. In this case, strain caused by manifests itself as spatially varying angular...
Perfect-crystal neutron interferometry which is analogous to Mach-Zehnder interferometry, uses Bragg diffraction form interfering paths. The measured phase shifts can be used probe many types of interactions whether it nuclear, electromagnetic, gravitational, or topological in nature. For a perfect-crystal interferometer preserve coherence, the crystal must possess high degree dimensional tolerance as well being relatively defect-free with minimal internal stresses. In past, interferometers...
Perfect-crystal neutron interferometry, which is analogous to Mach-Zehnder uses Bragg diffraction form interfering paths. The measured phase shifts can be used probe many types of interactions whether it nuclear, electromagnetic, gravitational, or topological in nature. For a perfect-crystal interferometer preserve coherence, the crystal must possess high degree dimensional tolerance as well being relatively defect-free with minimal internal stresses. In past, interferometers have been...
An electromagnetically driven normally closed valve for liquid helium is presented, which meant to regulate the input flow a 1 K pot. earlier design modified be (not actuated) and tuned durability reliability. A new feature presented prevents seat deformation at room temperature provides comfort intensive use.
We have designed a low temperature valve for liquid helium, which uses magnetic field gradient and permanent magnet to close. For closing, it presses small ruby ball onto Torlon seat. present that is easy build easily controlled via two wires. It has fast response, reliable, the advantage there no dead volume change on closing additional helium line required operate.
To measure the growth and melting mechanisms of solid 3He in magnetic field two magnetically ordered phases we need to deviation from equilibrium pressure very precisely. The measurements are temperature range below Néel transition, a up 9 T. We adapted Straty‐Adams type design Miura et al. [Rev. Sci. Instr. 64, 3215 (1993)], who were first use titanium as material for membrane. Titanium has high quality factor, is suitable field, not poisonous like beryllium. Our membrane diameter 14 mm,...
Haidinger’s brush is an entoptic image of a central oblong smudge elicited when the macular pigment preferentially absorbs specific direction polarized light. Because dependent on pigment, it may have value as screening tool for dysfunction. We examined whether healthy human observers could use to psychophysically discriminate between two beams structured light exhibiting different patterns spatially-dependent polarization, called spin-coupled Orbital Angular Momentum (OAM) states....
Neutrons have emerged as a unique probe at the forefront of modern material science, unrivaled in their penetrating abilities. A major challenge stems from fact that neutron optical devices are limited to refractive indices on order $n\approx 1 \pm 10^{-5}$. By exploiting advances precision manufacturing, we designed and constructed micro-meter period triangular grating with high aspect ratio $14.3$. The manufacturing quality is demonstrated white-light interferometric data microscope...