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Search Publications by: Dan Schmidt (Fed)

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Displaying 1 - 25 of 160

Towards Precision Spectroscopy of Antiprotonic Atoms for Probing Strong-field QED

January 15, 2025
Author(s)
Goncalo Baptista, Shikha Rathi, Michael Roosa, Quentin Senetaire, Jonas Sommerfeldt, Toshiyuki Azuma, Daniel Becker, Francois Butin, Ofir Eizenberg, Joseph Fowler, Hiroyuki Fujioka, Davide Gamba, Nabil Garroum, Mauro Guerra, Tadashi Hashimoto, Takashi Higuchi, Paul Indelicato, Jorge Machado, Kelsey Morgan, Francois Nez, Jason Nobles, Ben Ohayon, Shinji Okada, Daniel Schmidt, Daniel Swetz, Joel Ullom, Pauline Yzombard, Marco Zito, Nancy Paul
PAX (antiProtonic Atom X-ray spectroscopy) is a new experiment with the aim to test strong-field quantum electrodynamics (QED) effects by performing high-precision x-ray spectroscopy of antiprotonic atoms. By utilizing advanced microcalorimeter detection

Flexible superconducting wiring for integration with low temperature detector and readout fabrication

September 14, 2024
Author(s)
Galen O'Neil, Daniel Swetz, Joel Ullom, Daniel Schmidt, Joel Weber, John Mates, William Doriese, Mark Keller, Michael Vissers, Kelsey Morgan, Robinjeet Singh
We present a method of creating high density superconducting flexible wiring on flexible thin silicon substrates. The flexible wiring, called SOI flex, is created by depositing superconducting wiring on a silicon on insulator (SOI) wafer, selectively

Few-electron highly charged muonic Ar atoms verified by electronic K xrays

July 10, 2024
Author(s)
Takuma Okumura, Toshiyuki Azuma, Douglas Bennett, W. Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Tadashi Hashimoto, Ryota Hayakawa, Yuto Ichinohe, Paul Indelicato, Tadaaki Isobe, Sohtaro Kanda, Daiji Kato, Miho Katsuragawa, Naritoshi Kawamura, Yasushi Kino, Nao Kominato, Yasuhiro Miyake, Kelsey Morgan, Hirofumi Noda, Galen O'Neil, Shinji Okada, Kenichi Okutsu, Nancy Paul, Carl D. Reintsema, Toshiki Sato, Dan Schmidt, Kouichiro Shimomura, Patrick Strasser, Daniel Swetz, Tadayuki Takahashi, Shinichiro Takeda, Soshi Takeshita, Motonobu Tampo, Hideyuki Tatsuno, Tong Xiao-Min, Joel Ullom, Shin Watanabe, Shinya Yamada, Takuma Yamashita
Electronic K x rays emitted by muonic Ar atoms in the gas phase were observed using a superconducting transition-edge-sensor microcalorimeter. The high-precision energy spectra provided a clear signature of the presence of muonic atoms accompanied by a few

Effects of Stray Magnetic Field on Transition-edge Sensors in Gamma-ray Microcalorimeters

May 19, 2024
Author(s)
Mark Keller, Abigail Wessels, Dan Becker, Douglas Bennett, Matthew Carpenter, Mark Croce, Jozsef Imrek, Johnathon Gard, John Mates, Kelsey Morgan, Nathan Ortiz, Dan Schmidt, Katherine Schreiber, Daniel Swetz, Joel Ullom
Superconducting transition-edge sensors (TESs) used in x-ray and γ-ray microcalorimeters suffer degraded performance if cooled in a magnetic field B sufficient to trap flux in the sensors. We report measurements of γ-ray TESs before and after implementing

Characterization of Transition Edge Sensors for Decay Energy Spectrometry

May 16, 2024
Author(s)
Max Carlson, Ryan P. Fitzgerald, Galen O'Neil, Dan Schmidt
By using a superconducting Transition Edge Sensor (TES) to measure the thermal energy of individual decay events with high energy resolution (goal of 1 keV at 5 MeV), Decay Energy Spectrometry (DES) provides a unique fingerprint to identify each

Nanoscale Three-Dimensional Imaging of Integrated Circuits Using a Scanning Electron Microscope and Transition-Edge Sensor Spectrometer

April 30, 2024
Author(s)
Nathan Nakamura, Paul Szypryt, Amber Dagel, Bradley Alpert, Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Dylan Fox, Johnathon Gard, Ryan Goodner, James Zachariah Harris, Gene C. Hilton, Edward Jimenez, Burke Kernen, Kurt Larson, Zachary H. Levine, Daniel McArthur, Kelsey Morgan, Galen O'Neil, Christine Pappas, Carl D. Reintsema, Dan Schmidt, Peter Schulz, Daniel Swetz, Kyle Thompson, Joel Ullom, Leila R. Vale, Courtenay Vaughan, Christopher Walker, Joel Weber, Jason Wheeler
X-ray nanotomography is a powerful tool for the characterization of nanoscale materials and structures, but it is difficult to implement due to the competing requirements of X-ray flux and spot size. Due to this constraint, state-of-the-art nanotomography

Indium Bump Bonding: Advanced Integration Techniques for Low-Temperature Detectors and Readout

April 20, 2024
Author(s)
Tammy Lucas, John Biesecker, W.Bertrand (Randy) Doriese, Shannon Duff, Malcolm Durkin, Richard Lew, Joel Ullom, Michael Vissers, Dan Schmidt
We have examined the influence of bump shape and bonding pressure on low temperature electrical properties of indium bump connections including transition temperature, normal resistance, and superconducting critical current. We describe our test structures

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

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

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

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

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

Toward a New Primary Standardization of Radionuclide Massic Activity Using Microcalorimetry and Quantitative Milligram-Scale Samples

February 24, 2022
Author(s)
Ryan P. Fitzgerald, Bradley Alpert, Dan Becker, Denis E. Bergeron, Richard Essex, Kelsey Morgan, Svetlana Nour, Galen O'Neil, Dan Schmidt, Gordon A. Shaw, Daniel Swetz, R. Michael Verkouteren, Daikang Yan
We present a new paradigm for the primary standardization of radionuclide activity per mass of solution (Bq/g). Two key enabling capabilities are 4π decay-energy spectrometry using chip-scale sub-Kelvin microcalorimeters and direct realization of mass by

MICROMETROLOGY IN PURSUIT OF QUANTUM RADIATION STANDARDS

November 9, 2021
Author(s)
Ryan P. Fitzgerald, Zeeshan Ahmed, Denis E. Bergeron, Nikolai Klimov, Dan Schmidt, Ronald Tosh
With the recent redefinition of the SI base units in terms of constants of nature, the race is on to maximize achievable precision by developing primary standards based on quantum metrology, thereby to realize the Quantum SI. For the becquerel (Bq) and