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Displaying 676 - 700 of 143593

Magnetic transitions and magnetocaloric effect of Pr(Ga,Ge) compounds

September 1, 2024
Author(s)
Hao Li, Xinqi Zheng, Hui Wu, Juping Xu, Yawei Gao, Dingsong Wang, Jiawang Xu, Shanshan Zhen, Jiahao Gao, Yang Pan, Guyue Wang, Jingyan Zhang, He Huang, Yanfei Wu, Wen Yin, Shouguo Wang, Baogen Shen
PrGa compound was extensively studied due to its unique magnetic structure and magnetocaloric effect (MCE). In this study, the effect of Ge substitution for Ga atoms on the magnetic properties and MCE of the resulting Pr(Ga,Ge) compounds was systematically

Measurement of Chloride in Concrete by Prompt Gamma Neutron Activation

September 1, 2024
Author(s)
Richard A. Livingston, Preethi Sridhar, Neal Berke, Amde M. Amde, Heather H. Chen-Mayer
Prompt Gamma Activation Analysis (PGAA) is an elemental analysis method based on radiative neutron capture that is isotope-specific and has a high sensitivity to chlorine (Cl). To evaluate the feasibility of replacing the conventional wet chemistry method

Calibration of Autler-Townes based electrometry in Rydberg states of alkali atoms

August 30, 2024
Author(s)
Noah Schlossberger, Nikunjkumar Prajapati, Alexandra Artusio-Glimpse, Samuel Berweger, Matthew Simons, William Watterson, Dangka Shylla, Christopher Holloway
Highly excited states of alkali atoms are a powerful tool for making SI-traceable electric field measurements without the need for an external reference. However, the calibration of these measurements suffers from ambiguity in which transition dipole

Detecting Firefighter's Tenability Utilizing Machine Learning

August 30, 2024
Author(s)
Qi Tong, Hongqiang FANG, Eugene Yujun Fu, Wai Cheong Tam, Thomas Gernay
The proposed research aims to leverage machine learning to detect thermal operating classes and improve the tenability of firefighters in a commercial building. A total of 3000 simulations are run with FDS to collect temperature from heat detectors. The

Differential Measurements of an AC Source with a Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Alain Rufenacht, Raegan Johnson, Anna Fox, Nathan Flowers-Jacobs, Charlie Burroughs, Samuel Benz, Paul Dresselhaus, STEPHANE SOLVE, Jesus Mejia
This paper describes differential sampling measurements of an ac source and a Josephson arbitrary waveform synthesizer (JAWS). A new iterative approach for aligning the phases of the JAWS and the source waveforms was implemented to minimize the

Digitizer Linearity Measurement with a Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Jesus Mejia, Alain Rufenacht, Raegan Johnson, Anna Fox, Nathan Flowers-Jacobs, Samuel Benz, Paul Dresselhaus
This article examines the non-linearity and gain error of a commercial digitizer on the 100 mV range with a Josephson Arbitrary Waveform Synthesizer (JAWS) as a reference. Different digitizer input filter settings were studied, and the shortest aperture of

Drug Detection, Analysis, and Monitoring Workshop Report

August 30, 2024
Author(s)
Edward Sisco
This report is a summary of a workshop convened to capture the analytical and data challenges inherent to the detection, identification, and monitoring of illicit drugs in the United States – specifically highlighting current practices, challenges, and

Dual-Frequency-Bias Programmable Josephson Voltage Standard Circuit Design

August 30, 2024
Author(s)
Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
This paper presents a new 2 V programmable Josephson voltage standard circuit with dual microwave frequency input. This design provides three main features: (1) output voltages with nanovolt resolution, (2) the ability to perform a microwave frequency self

Measuring VHF Detector Linearity using a Quantum-Based Source

August 30, 2024
Author(s)
Jeremy Thomas, Nathan Flowers-Jacobs, Anna Fox, Alain Rufenacht, Paul Dresselhaus
We demonstrate the use of a Josephson Arbitrary Waveform Synthesizer (JAWS) for linearity measurements of two instruments: an RF power sensor and a fast ADC. The VHF-JAWS source consists of a chip with 12,810Josephson junctions located in a cryocooler and

Optimization of Wye-D-Type Quantum Hall Resistance Standard

August 30, 2024
Author(s)
Yanfei Yang, Dean G. Jarrett, Alireza Panna, Albert Rigosi, David B. Newell, Randolph Elmquist, Cheng Hsueh Yang, Ngoc Thanh Mai Tran
Theoretically wye-delta transformation can be used to realize ultra-high resistances up to PΩ. For graphene-based quantum Hall array resistance standards fabricated to utilize the wye-delta transformation, a few challenges present themselves, including the

Progress in the Kibble Dynamic Force Reference

August 30, 2024
Author(s)
Jared Strait, Akobuije Chijioke
We present progress in the development of a dynamic force reference instrument (KDFR) based on the Kibble principle. We describe the operating principle and design of the KDFR and discuss how the design for alternating current (AC) force measurements

Pulse Patterns for the Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Nathan Flowers-Jacobs, Raegan Johnson, Jeremy Thomas, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
Δ-sigma algorithms are used to determine the desired sequence of quantum-based voltage pulses used by the Josephson Arbitrary Waveform Synthesizer (JAWS) to create calculable voltage waveforms. We describe typical settings used for synthesizing JAWS audio

Single-cryostat integration of the quantum anomalous Hall and Josephson effects

August 30, 2024
Author(s)
Jason Underwood, Linsey Rodenbach, Ngoc Thanh Mai Tran, Alireza Panna, Zachary Barcikowski, Molly Andersen, Peng Zhang, Lixuan Tai, Randolph Elmquist, Dean Jarrett, David Goldhaber-Gordon, David Newell, Albert Rigosi
By directly integrating a quantum anomalous Hall resistor (QAHR) and a programmable Josephson voltage standard (PJVS) into a single cryostat, we have implemented a quantum electrical reference that provides a realization of the volt, ohm, and ampere in

Stability Study of ac Voltage Source using Josephson Voltage Standards

August 30, 2024
Author(s)
Ghislain Granger, Waldemar G. Kuerten Ihlenfeld, Alain Rufenacht, Nathan Flowers-Jacobs, Anna Fox, Raegan Johnson, Jesus Mejia
The stability of an ac voltage source fabricated at the National Research Council Canada (NRC) is investigated. NRC uses differential sampling to monitor the source voltage with respect to a step-wise approximated reference waveform generated by the

Assessing girth weld quality of pipeline steels and their susceptibility to hydrogen embrittlement

August 28, 2024
Author(s)
Zack Buck, Newell Moser, Nicholas Derimow, May Ling Martin, Damian Lauria, Enrico Lucon, Douglas Stalheim, Peter Bradley, Matthew Connolly
Hydrogen has long been considered a viable carbon-free option for ever-increasing societal desires to transform our energy infrastructure towards more renewable and alternative technologies. However, the effects of hydrogen-assisted damage mechanisms that

Continuum of Spin Excitations in the Exactly Solvable Triangular-Lattice Spin Liquid CeMgAl11O19

August 28, 2024
Author(s)
Bin Gao, Tong Chen, Chunxaio Liu, Mason Klemm, Shu Zhang, Zhen Ma, Xianghan Xu, CHOONGJAE WON, Dongzhe Dai, Gregory McCandless, Maiko Kofu, Naoki Murai, Stephen Moxim, Jason Ryan, Xiaozhou Huang, Xiaoping Wang, Julia Chan, Shiyan Li, Sang-Wook Cheong, Oleg Tchernyshyov, Leon Balents, Pengcheng Dai
In magnetically ordered insulators, elementary quasiparticles manifest as spin waves - collective motions of localized magnetic moments that propagate through the lattice - observed via inelastic neutron scattering. In effective spin- 1/2 systems where

Mechanical Metallurgy on Columbia Gas X100 Experimental Pipe

August 28, 2024
Author(s)
Dash Weeks, Ryan White, Jake Benzing, Enrico Lucon, Nicholas Derimow, Ashley Kroon, Robert Smith
This study evaluates the material properties of an X100 pipeline steel extracted from an experimental transmission pipeline section placed into service in the 1960s. The purpose is to compare these properties with current X100 steel standards

Multifaceted Neuroimaging Data Integration via Analysis of Subspaces

August 28, 2024
Author(s)
Andrew Ackerman, Zhengwu Zhang, Jan Hannig, Jack Prothero, J.S. Marron
Neuroimaging studies, such as the Human Connectome Project (HCP), often collect multifaceted and multi-block data to study the complex human brain. However, these data are often analyzed in a pairwise fashion, which can hinder our understanding of how
Displaying 676 - 700 of 143593