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Search Publications by: Joel Ullom (Fed)

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Displaying 1 - 25 of 170

A tabletop x-ray tomography instrument for nanometer-scale imaging: demonstration of the 1,000-element transition-edge sensor subarray

August 1, 2023
Author(s)
Paul Szypryt, Nathan J. Nakamura, Dan Becker, Douglas Bennett, Amber L. Dagel, W.Bertrand (Randy) Doriese, Joseph Fowler, Johnathon Gard, J. Zachariah Harris, Gene C. Hilton, Jozsef Imrek, Edward S. Jimenez, Kurt W. Larson, Zachary H. Levine, John Mates, Daniel McArthur, Luis Miaja Avila, Kelsey Morgan, Galen O'Neil, Nathan Ortiz, Christine G. Pappas, Dan Schmidt, Kyle R. Thompson, Joel Ullom, Leila R. Vale, Michael Vissers, Christopher Walker, Joel Weber, Abigail Wessels, Jason W. Wheeler, Daniel Swetz
We report on the 1,000-element transition-edge sensor (TES) x-ray spectrometer implementation of the TOMographic Circuit Analysis Tool (TOMCAT). TOMCAT combines a high spatial resolution scanning electron microscope (SEM) with a highly efficient and

Single Flux Quantum-Based Digital Control of Superconducting Qubits in a Multi-Chip Module

June 24, 2023
Author(s)
Chuanhong Liu, Robert McDermott, Britton Plourde, Andrew Ballard, Jonathan DuBois, Pete Hopkins, David Olaya, John Biesecker, Samuel P. Benz, Dan Schmidt, Joel Ullom
The single flux quantum (SFQ) digital superconducting logic family has been proposed as a practical approach for controlling next-generation superconducting qubit arrays with more favorable scaling properties compared to conventional microwave-based

Systematic Improvements in Transmon Qubit Coherence enabled by Niobium Surface Encapsulation

June 14, 2023
Author(s)
Mustafa BAL, Akshay Murthy, Francesco Crisa, Shaojiang Zhu, Florent Lecocq, Joe Aumentado, Joel Ullom, Pete Hopkins
We present a novel transmon qubit fabrication technique that yields systematic improvements in T1 coherence times. In this study, the devices are fabricated using a novel encapsulation strategy that involves passivating the surface of niobium and thereby

Proof-of-Principle Experiment for Testing Strong-Field Quantum Electrodynamics with Exotic Atoms: High Precision X-Ray Spectroscopy of Muonic Neon

April 27, 2023
Author(s)
Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Kelsey Morgan, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Takuma Okumura
To test the bound-state quantum electrodynamics (BSQED), we have performed high precision x- ray spectroscopy of the 5g→4f and 5f→4d transitions (BSQED contribution of 2.4 eV and 5.2 eV, respectively) of muonic neons in the low-pressure gas phase under the

A Tabletop X-Ray Tomography Instrument for Nanometer-Scale Imaging: Reconstructions

April 14, 2023
Author(s)
Zachary H. Levine, Bradley Alpert, Amber Dagel, Joseph Fowler, Edward Jiminez, Nathan J. Nakamura, Daniel Swetz, Paul Szypryt, Kyle Thompson, Joel Ullom
We show three-dimensional reconstructions of a region of an integrated circuit from a 130 nm copper process. The reconstructions employ x-ray computed tomography, measured with a new and innovative high-magnification x-ray microscope. The instrument uses a

Symmetric time-division-multiplexed SQUID readout with two-layer switches for future TES observatories

April 4, 2023
Author(s)
Malcolm Durkin, Scott Backhaus, Simon Bandler, James Chervenak, Ed Denison, W.Bertrand (Randy) Doriese, Johnathon Gard, Gene C. Hilton, Richard Lew, Tammy Lucas, Carl D. Reintsema, Dan Schmidt, Stephen Smith, Joel Ullom, Leila R. Vale, Michael Vissers, Nicholas Wakeham
Time-division multiplexing (TDM) of transition-edge-sensor (TES) microcalorimeters is being developed as the readout tech-nology for the Athena X-ray integral field unit (X-IFU) and is under consideration for future TES-bolometer missions like CMB-S4. We

Role of Non-Temperature-Gradient Power Flow Terms in Low-Temperature Regenerators

December 1, 2022
Author(s)
Ryan Snodgrass, Joel Ullom, Scott Backhaus
The total power flow through cryocooler regenerators is key to their performance because it reduces the cooling available at the cold heat exchanger. At temperatures near 4 K, the real-fluid properties of helium and the finite-heat-capacity of regenerator

Indium Bump Process for Low-Temperature Detectors and Readout

May 20, 2022
Author(s)
Tammy Lucas, John Biesecker, W.Bertrand (Randy) Doriese, Shannon Duff, Gene C. Hilton, Joel Ullom, Michael Vissers, Dan Schmidt
We describe our indium bump process for low-temperature detectors and associated readout. A titanium nitride under bump metallization layer (UBM) is reactively sputtered onto wiring pads as a diffusion barrier and adhesion layer. Indium is thermally

Performance of a Kinetic-Inductance Traveling-Wave Parametric Amplifier at 4 Kelvin: Toward an Alternative to Semiconductor Amplifiers

April 5, 2022
Author(s)
Maxime Malnou, Joe Aumentado, Michael Vissers, Jordan Wheeler, Johannes Hubmayr, Joel Ullom, Jiansong Gao
Most microwave readout architectures in quantum computing or sensing rely on a semiconductor amplifier at 4\,K, typically a high-electron mobility transistor (HEMT). Despite its remarkable noise performance, a conventional HEMT dissipates several

Measurements of Strong-Interaction Effects in Kaonic-Helium Isotopes at sub-eV Precision with x-ray microcalorimeters

March 18, 2022
Author(s)
Tadashi Hashimoto, S Aikawa, T. Akaishi, M Bazzi, Douglas Bennett, M Berger, D Bosnar, A. D. Butt, C. Curceanu, W.Bertrand (Randy) Doriese, Malcolm Durkin, Y Ezoe, Joseph Fowler, H. Fujioka, Johnathon Gard, C Guaraldo, F.P. Gustafsson, C. Han, R Hayakawa, R. S. Hayano, T Hayashi, J. Hays-Wehle, Gene C. Hilton, T Hiraiwa, M Hiromoto, Y Ichinoge, M Iio, Y Iizawa, M Iliescu, S Ishimoto, Y Ishisaki, K Itahashi, M Iwasaki, Y Ma, T Murakami, T Nishi, H Noda, K Nomura, H Noumi, K Ooi, H Outa, K Piscicchia, Carl D. Reintsema, Y Sada, S Okada, Galen O'Neil, Dan Schmidt, Daniel Swetz, Joel Ullom, S Yamada, J Uhlig
We have measured the 3 d→ 2 p transition x rays of kaonic He 3 and He 4 atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4 (stat)±0.2 (syst) eV

Brominated nanoscale diamond enables room temperature and catalysis free functionalization chemistry

January 27, 2022
Author(s)
Cynthia Melendrez, Jorge Lopez-Rosas, Tsz Cheung, Camron Stokes, Sang-Jun Lee, Jan Vavra, Helena Raabova, Vaclav Vanek, Sami Sainio, Dennis Nordlund, W.Bertrand (Randy) Doriese, Galen O'Neil, Daniel Swetz, Joel Ullom, Kent Irwin, Peter Cigler, Polo Tran, Halim Muhammad, Virginia Altoe, Charles Titus, Jocelyn Valenzuela, Grace Jeanpierre, Abraham Wolcott
Bromination of diamond surfaces has not been explored and can potentially open new avenues for increased chemical reactivity. Aerobically oxidized high-pressure high-temperature nanoscale diamond (ND) is a widely used host for the nitrogen vacancy centers

Sub-kelvin thermometer for on-chip measurements of microwave devices utilizing two-level systems in superconducting microresonators

November 13, 2021
Author(s)
Jordan Wheeler, Michael Vissers, Maxime Malnou, Johannes Hubmayr, Joel Ullom, Jiansong Gao
The design, implementation, and sensitivity of a new microwave multiplexable superconducting resonator thermometer based on two-level-systems are presented. The thermometer operates from 1 K to 50 mK and has the potential to measure down to 5 mK. The

Proceedings of the 2nd CREST Nano-Virtual-Labs Joint Workshop on Superconductivity

October 12, 2021
Author(s)
Kent D. Irwin, James A. Beall, W.Bertrand (Randy) Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, John Mates, Nathan A. Tomlin, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Joel Ullom, Leila R. Vale
Superconductivity is a powerful tool for the detection of electromagnetic radiation and the energy in particle interactions. One leading superconducting detector technology is the superconducting transition-edge sensor (TES), which uses a superconducting

Design of a 3000 pixel transition-edge sensor x-ray spectrometer for microcircuit tomography

August 1, 2021
Author(s)
Paul Szypryt, Douglas Bennett, William J. Boone, Amber L. Dagel, G Dalton, William Doriese, Malcolm Durkin, Joseph Fowler, Edward Garboczi, Jonathon D. Gard, Gene Hilton, Jozsef Imrek, E S. Jimenez, Vincent Y. Kotsubo, K Larson, Zachary H. Levine, John Mates, D McArthur, Kelsey Morgan, Nathan J. Nakamura, Galen O'Neil, Nathan Ortiz, Christine G. Pappas, Carl Reintsema, Dan Schmidt, Daniel Swetz, K R. Thompson, Joel Ullom, C Walker, Joel C. Weber, Abigail Wessels, J W. Wheeler
Feature sizes in integrated circuits have decreased substantially over time, and it has become increasingly difficult to three-dimensionally image these complex circuits after fabrication. This can be important for process development, defect analysis, and

De-excitation dynamics of muonic atoms revealed by high precision spectroscopy of electronic K x rays using a superconducting transition-edge sensor microcalorimeter

July 27, 2021
Author(s)
Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Kelsey Morgan, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Toshiyuki Azuma, Pietro Caradonna, I-Huan Chiu, Tadashi Hashimoto, Ryota Hayakawa, Yuto Ichinohe, Paul Indelicato, TadaAki Isobe, Sohtaro Kanda, Daiji Kato, Miho Katsuragawa, Naritoshi Kawamura, Yasushi Kino, Kenya Kubo, Kairi Mine, Yasuhiro Miyake, Kazuhiko Ninomiya, Hirofumi Noda, Shinji Okada, Takuma Okumura, Kenichi Okutsu, Takahito Osawa, Nancy Paul, Kouichiro Shimomura, Patrick Strasser, Hirotaka Suda, Tadayuki Takahashi, Shinichiro Takeda, Soshi Takeshita, Motonobu Tampo, Hideyuki Tatsuno, XiaoMin Tong, Yasuhiro Ueno, Shin Watanabe, Shinya Yamada
We observed electronic K x rays emitted from muonic iron atoms using a superconducting transition-edge-type sensor microcalorimeter. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic

A Model for Excess Johnson Noise in Superconducting Transition-edge Sensors

May 18, 2021
Author(s)
Abigail Wessels, Kelsey Morgan, Dan Becker, Johnathon Gard, Gene C. Hilton, John Mates, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila R. Vale, Douglas Bennett
Transition-Edge Sensors (TESs) are two-dimensional superconducting films used to detect energy or power. These detectors are voltage biased in the superconducting transition where the film resistance is both finite and a strong function of temperature

Gamma and Decay Energy Spectroscopy Measurements of Trinitite

April 7, 2021
Author(s)
David Mercer, Katrina Koehler, Mark Croce, Andrew Hoover, Philip Hypes, Stosh Kozimor, Veronika Mocko, Paul Saey, Dan Schmidt, Joel Ullom
We report gamma ray spectroscopy measurements of trinitite samples and analogous samples obtained from detonation sites in Nevada and Semipalatinsk, as well as in situ measurements of topsoil at the Trinity site. We also report the first isotopic