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Search Publications by

Joel Ullom (Fed)

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Displaying 1 - 25 of 145

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

November 13, 2021
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
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
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

Gamma and Decay Energy Spectroscopy Measurements of Trinitite

April 7, 2021
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

Absolute energies and emission line shapes of the x-ray lines of lanthanide metals

February 1, 2021
Joseph Fowler, Galen O'Neil, Bradley K. Alpert, Douglas Bennett, Edward V. Denison, William Doriese, Gene Hilton, Lawrence T. Hudson, Young I. Joe, Kelsey Morgan, Daniel Schmidt, Daniel Swetz, Csilla I. Szabo-Foster, Joel Ullom
We use an array of transition-edge sensors, cryogenic microcalorimeters with 4 eV energy resolution, to measure the x-ray emission-line profiles of four elements of the lanthanide series: praseodymium, neodymium, terbium, and holmium. The spectrometer also

Broadband high-energy resolution hard x-ray spectroscopy using transition edge sensors at SPring-8

January 12, 2021
Shinya Yamada, Yuto Ichinohe, Hideyuki Tatsuno, Ryota Hayakawa, Hirotaka Suda, Takaya Ohashi, Yoshitaka Ishisaki, Tomoya Uruga, Oki Sekizawa, Kiyofumi Nitta, Yoshio Takahashi, Takaaki Itai, Hiroki Suga, Makoto Nagasawa, Masato Tanaka, Minako Kurisu, Tadashi Hashimoto, Douglas Bennett, Edward V. Denison, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Galen O'Neil, Kelsey Morgan, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila R. Vale, Shinji Okada, Takuma Okumura, Toshiyuki Azuma, Toru Tamagawa, Tadaaki Isobe, Satoshi Kohjiro, Hirofumi Noda, Keigo Tanaka, Akimichi Taguchi, Yuki Imai, Kosuke Sato, Tasuku Hayashi, Teruhiko Kashiwabara, Kohei Sakata
We have succeeded in operating a transition-edge sensor (TES) spectrometer and evaluating its performance at the SPring-8 synchrotron x-ray light source. The TES spectrometer consists of a 240 pixel National Institute of Standards and Technology (NIST) TES

Improved plutonium and americium photon branching ratios from microcalorimeter gamma spectroscopy

October 11, 2020
M. D. Yoho, K. E. Koehler, Dan Becker, Douglas Bennett, M. H. Carpenter, M. P. Croce, J. D. Gard, John Mates, D. J. Mercer, Nathan Ortiz, Dan Schmidt, C. M. Smith, Daniel Swetz, A. D. Tollefson, Joel Ullom, Leila R. Vale, Abigail Wessels, D. T. Vo
Photon branching ratios are critical input data for activities such as nuclear materials protection and accounting because they allow material compositions to be extracted from measurements of gamma-ray intensities. Uncertainties in these branching ratios

Compact 1.7 K Cryocooler for Superconducting Nanowire Single-Photon Detectors

June 18, 2020
Vincent Y. Kotsubo, Joel N. Ullom, Sae Woo Nam
State-of-the-art superconductor-based cryogenic detector systems are being installed at numerous research facilities worldwide and are achieving world-record sensitivities in a variety of applications. Implementation has been greatly facilitated by closed

A Predictive Control Algorithm for Time-Division-Multiplexed Readout of TES Microcalorimeters

January 28, 2020
Malcolm S. Durkin, Galen C. O'Neil, William B. Doriese, Johnathon D. Gard, Gene C. Hilton, Jozsef Imrek, Nathan J. Ortiz, Carl D. Reintsema, Robert W. Stevens, Daniel S. Swetz, Joel N. Ullom
Time division multiplexing (TDM) uses a digital flux-locked loop (DFLL) to linearize each first-stage SQUID amplifier. Presently, the dynamic range of our TDM systems is limited by the use of a proportional-integral controller to maintain the DFLL. In this

Demonstration of 220/280 GHz Multichroic Feedhorn-Coupled TES Polarimeter

January 3, 2020
Samantha L. Walker, Carlos E. Sierra, Jason E. Austermann, James A. Beall, Daniel T. Becker, Bradley J. Dober, Shannon M. Duff, Gene C. Hilton, Johannes Hubmayr, Jeffrey L. Van Lanen, Jeff McMahon, Sara M. Simon, Joel N. Ullom, Michael R. Vissers
We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in

A transition-edge sensor-based x-ray spectrometer for the study of highly charged ions at the National Institute of Standards and Technology electron beam ion trap

December 16, 2019
Paul Szypryt, Galen C. O'Neil, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Douglas A. Bennett, William B. Doriese, Malcolm S. Durkin, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kelsey M. Morgan, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom, Yuri Ralchenko
We report on the design, commissioning, and initial measurements of a Transition-Edge Sensor (TES) x-ray spectrometer for the Electron Beam Ion Trap (EBIT) at the National Institute of Standards and Technology (NIST). Over the past few decades, the NIST

On Low-Energy Tail Distortions in the Detector Response Function of X-Ray Microcalorimeter Spectrometers

November 21, 2019
Galen C. O'Neil, Paul Szypryt, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Young I. Joe, Daniel S. Swetz, Daniel R. Schmidt, William B. Doriese, Johnathon D. Gard, Carl D. Reintsema, Joel N. Ullom, John S. Villarrubia, Yuri Ralchenko
We use narrow spectral lines from the X-ray spectra of various highly charged ions to measure low-energy tail-like deviations from a Gaussian response function in a microcalorimeter X-ray spectrometer with Au absorbers at energies from 650 to 3320 eV. We

Crosstalk in microwave SQUID multiplexers

November 15, 2019
John A. Mates, Daniel T. Becker, Douglas A. Bennett, Bradley J. Dober, Johnathon D. Gard, Gene C. Hilton, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
Low-temperature detector technologies provide extraordinary sensitivity for applications ranging from precision measurements of the cosmic microwave background to high-resolution, high-rate x-ray, and c-ray spectroscopy. To utilize this sensitivity, new

A Robust Principal Component Analysis for Outlier Identification in Messy Microcalorimeter Data

November 12, 2019
Joseph W. Fowler, Bradley K. Alpert, Young I. Joe, Galen C. O'Neil, Daniel S. Swetz, Joel N. Ullom
A principal component analysis (PCA) of clean microcalorimeter pulse records can be a first step beyond statistically optimal linear filtering of pulses toward a fully nonlinear analysis. For PCA to be practical on spectrometers with hundreds of sensors

Expanding the Capability of Microwave Multiplexed Readout for Fast Signals in Microcalorimeters

November 11, 2019
Kelsey M. Morgan, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, Jozsef Imrek, John A. Mates, Christine G. Pappas, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Joel C. Weber, Abigail L. Wessels, Daniel S. Swetz
Microwave SQUID multiplexing has become a key technology for reading out large arrays of X-ray and gamma-ray microcalorimeters with mux factors of 100 or more. The desire for fast X-ray pulses that accommodate photon counting rates of hundreds or thousands

Soft X-ray spectroscopy with transition-edge sensors at Stanford Synchrotron Radiation Lightsource beamline 10-1

November 5, 2019
Sang-Jun Lee, Charles Titus, Roberto A. Mori, Michael Baker, Douglas Bennett, Hsiao-Mei Cho, W.Bertrand (Randy) Doriese, Joseph Fowler, Kelly J. Gaffney, Allesandro Gallo, Johnathon Gard, Gene C. Hilton, Hoyoung Jang, Young I. Joe, Christopher Kenney, Jason Knight, Thomas Kroll, Jun-Sik Lee, Dale Li, Donhui Lu, Ronald Marks, Michael Minitti, Kelsey Morgan, Ogasawara Hirohito, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Dimosthenis Sokaras, Joel Ullom, Tsu-Chien Weng, Christopher Williams, Betty A. Young, Daniel Swetz, Kent D. Irwin, Dennis Nordlund
We present results obtained with a new soft X-ray spectrometer based on transition-edge sensors (TESs) composed of Mo/Cu bilayers coupled to bismuth absorbers. This spectrometer simultaneously provides excellent energy resolution, high detection efficiency

Controlling the thermal conductance of silicon nitride membranes at 100 mK temperatures with patterned metal features

August 2, 2019
Xiaohang Zhang, Shannon M. Duff, Gene C. Hilton, Peter J. Lowell, Kelsey M. Morgan, Daniel R. Schmidt, Joel N. Ullom
Freestanding micromachined membranes are often used for thermal isolation in electronic devices such as photon sensors. The degree of thermal isolation plays an important role in determining device performance, and so the ability to suppress the thermal

Configurable error correction of code-division multiplexed TES detectors with a cryotron switch

June 10, 2019
Joel C. Weber, Joseph W. Fowler, Malcolm S. Durkin, Kelsey M. Morgan, John A. Mates, Douglas A. Bennett, William B. Doriese, Daniel R. Schmidt, Gene C. Hilton, Daniel S. Swetz, Joel N. Ullom
The development of a superconducting analog to the transistor with extremely low power dissipation will accelerate the proliferation of low-temperature circuitry operating in the milliKelvin regime. The thin-film, magnetically actuated cryotron switch is a

A TES X-ray Spectrometer for NSENSE

March 25, 2019
Christine G. Pappas, Malcolm S. Durkin, Joseph W. Fowler, Kelsey M. Morgan, Joel N. Ullom, William B. Doriese, Gene C. Hilton, Galen C. O'Neil, Daniel R. Schmidt, Paul Szypryt, Daniel S. Swetz
The Non-destructive Statistical Estimation of Nanoscale Structures and Electronics NSENSE instrument for IARPAs Rapid Analysis of Various Emerging Nanoelectronics RAVEN program is a tabletop X-ray tomography prototype designed for three-dimensional imaging

Microwave SQUID multiplexing for the Lynx x-ray microcalorimeter

March 22, 2019
Douglas A. Bennett, John A. Mates, Simon R. Bandler, Daniel T. Becker, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, K D. Irwin, Kelsey M. Morgan, Carl D. Reintsema, Kazuhiro Sakai, Daniel R. Schmidt, Stephen J. Smith, Daniel S. Swetz, Joel N. Ullom, Leila R. Vale, Abigail L. Wessels
The Lynx x-ray microcalorimeter (LXM) is an imaging spectrometer for the Lynx satellite mission, an x-ray telescope being considered by NASA to be a new flagship mission. Lynx will enable unique astrophysical observations into the x-ray universe due to its

Demonstration of Athena X-IFU Compatible 40-Row Time-Division-Multiplexed Readout

March 19, 2019
Malcolm S. Durkin, Joseph S. Adams, Simon R. Bandler, James A. Chervenak, Saptarshi Chaudhuri, Carl S. Dawson, Edward V. Denison, William B. Doriese, Shannon M. Duff, F. M. Finkbeiner, C. T. FitzGerald, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kent D. Irwin, Young I. Joe, R. L. Kelley, Caroline A. Kilbourne, A. R. Miniussi, Kelsey M. Morgan, Galen C. O'Neil, Christine G. Pappas, F. S. Porter, Carl D. Reintsema, David A. Rudman, Kazuhiro Sakai, Stephen J. Smith, Robert W. Stevens, Daniel S. Swetz, Paul Szypryt, Joel N. Ullom, Leila R. Vale, N. Wakeham, Joel C. Weber, B. A. Young
Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for european space agency's Athena satellite mission