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Publications

Search Publications by Joel Ullom

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Displaying 26 - 50 of 142

Tile-and-trim micro-resonator array fabrication optimized for high multiplexing factors

November 8, 2018
Author(s)
Christopher M. McKenney, Jason E. Austermann, James A. Beall, Bradley J. Dober, Shannon M. Duff, Jiansong Gao, Gene C. Hilton, Johannes Hubmayr, Dale Li, Joel N. Ullom, Jeffrey L. Van Lanen, Michael R. Vissers
We present a superconducting micro-resonator array fabrication method that is scalable and reconfigurable and has been optimized for high multiplexing factors. The method uses uniformly sized tiles patterned on stepper photolithography reticles as the

A 300-mK Test Bed for Rapid Characterization of Microwave SQUID Multiplexing Circuits

August 3, 2018
Author(s)
Abigail L. Wessels, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, Johannes Hubmayr, Norman Jarosik, Vincent Y. Kotsubo, John A. Mates, Joel N. Ullom
Microwave SQUID multiplexing is a promising technique for multiplexing large arrays of transition edge sensors. A major bottleneck in the development and distribution of microwave SQUID multiplexer chips occurs in the time-intensive design testing and

Low-Temperature Detectors for CMB Imaging Arrays

August 3, 2018
Author(s)
Johannes Hubmayr, Jason E. Austermann, James A. Beall, Daniel T. Becker, Bradley J. Dober, Shannon M. Duff, Jiansong Gao, Gene C. Hilton, Christopher M. McKenney, Joel N. Ullom, Jeffrey L. Van Lanen, Michael R. Vissers
We review advances in low-temperature detector (LTD) arrays for cosmic microwave background (CMB) polarization experiments, with a particular emphasis on imaging arrays. We briefly motivate the science case, which has spurred a large number of independent

A Highly Linear Calibration Metric for TES X-ray Microcalorimeters

August 2, 2018
Author(s)
Christine G. Pappas, Joseph W. Fowler, Douglas A. Bennett, William B. Doriese, Young I. Joe, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz
Transition-edge sensor X-ray microcalorimeters are usually calibrated empirically, as the most widely-used calibration metric, optimal filtered pulse height (OFPH), in general has an unknown dependance on photon energy, Eγ. Because the calibration function

A Scalable Readout for Microwave SQUID Multiplexing of Transition-Edge Sensors

July 9, 2018
Author(s)
Johnathon D. Gard, Daniel T. Becker, Douglas A. Bennett, Joseph W. Fowler, Gene C. Hilton, John A. Mates, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The readout requirements for instruments based on transition-edge sensors (TESs) have dramatically increased over the last decade as demand for systems with larger arrays and faster sensors has grown. Emerging systems are expected to contain many thousands

Resonator Stabilization Architecture to Suppress Switching Transient Crosstalk in I-CDM

May 30, 2018
Author(s)
Malcolm S. Durkin, Joel C. Weber, William B. Doriese, Gene C. Hilton, Daniel S. Swetz, Joel N. Ullom
The ever-increasing sizes of transition-edge sensor (TES) microcalorimeter arrays motivates improved multiplexed readout with large multiplexing factors, low power dissipation, and low levels of crosstalk. Current-summed code division multiplexing (I-CDM)

Approaches to the Optimal Nonlinear Analysis of Microcalorimeter Pulses

March 8, 2018
Author(s)
Joseph W. Fowler, Christine G. Pappas, Bradley K. Alpert, William B. Doriese, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz
We consider how to analyze microcalorimeter pulses for quantities that are nonlinear in the data, while preserving the signal-to-noise advantages of linear optimal filtering. We apply the approach to compute the electrothermal feedback energy deficit (the

Millimeter-Wave Polarimeters Using Kinetic Inductance Detectors for TolTEC and Beyond

March 8, 2018
Author(s)
Jason E. Austermann, James A. Beall, Sean A. Bryan, Bradley J. Dober, Jiansong Gao, Gene C. Hilton, Johannes Hubmayr, Phillip Mauskopf, Christopher M. McKenney, S M. Simon, Joel N. Ullom, Michael R. Vissers, G W. Wilson
Microwave kinetic inductance detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the

Superconducting micro-resonator arrays with ideal frequency spacing

December 20, 2017
Author(s)
Xiangliang Liu, Weijie Guo, Y Wang, M Dai, L F. Wei , Bradley J. Dober, Christopher M. McKenney, Gene C. Hilton, Johannes Hubmayr, Jason E. Austermann, Joel N. Ullom, Jiansong Gao, Michael R. Vissers
We present a wafer trimming technique for producing superconducting micro-resonator arrays with highly uniform frequency spacing. With the light-emitting diode mapper technique demonstrated previously, we first map the measured resonance frequencies to the

Dependence of transition width on current and critical current in transition-edge sensors

December 7, 2017
Author(s)
Kelsey M. Morgan, Christine G. Pappas, Douglas A. Bennett, Johnathon D. Gard, James P. Hays-Wehle, Gene C. Hilton, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Daniel S. Swetz
If transition-edge sensor (TES) X-ray detectors are to be useful in photon-rich environments,they must maintain high resolving power when pulse durations are engineered to be short, which is usually accomplished by increasing the thermal conductance (G)to

L-Edge Spectroscopy of Dilute, Radiation-Sensitive Systems Using a Transition-Edge-Sensor Array

December 7, 2017
Author(s)
Daniel S. Swetz, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom
We present X-ray absorption spectroscopy and resonant inelastic X-ray scattering (RIXS) measurements on the iron L-edge of 0.5 mM aqueous ferricyanide. These measurements demonstrate the ability of high-throughput transition- edge-sensor (TES)

Simultaneous readout of 128 X-ray and Gamma-ray Transition-edge Microcalorimeters using Microwave SQUID Multiplexing

August 8, 2017
Author(s)
John A. Mates, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, James P. Hays-Wehle, Joseph W. Fowler, Gene C. Hilton, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
The number of elements in most cryogenic sensor arrays is limited by the technology available to multiplex signals from the array into a smaller number of wires and readout amplifiers. The largest demonstrated arrays of transition-edge sensor (TES)

A Reassessment of Absolute Energies of X-ray L Lines of Lanthanide Metals

June 28, 2017
Author(s)
Bradley K. Alpert, William B. Doriese, Gene C. Hilton, Lawrence T. Hudson, Young Il Joe, Kelsey M. Morgan, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Csilla I. Szabo-Foster, Joel N. Ullom, Joseph W. Fowler, Galen C. O'Neil, Douglas A. Bennett
We introduce a new technique for determining x-ray fluorescence line energies and widths, and we present measurements made with this technique of 22 x-ray L lines from lanthanide-series elements. The technique uses arrays of transition-edge sensors

Counting Near Infrared Photons with Microwave Kinetic Inductance Detectors

May 22, 2017
Author(s)
Jiansong Gao, Michael R. Vissers, Joel N. Ullom, Johannes Hubmayr, Joseph W. Fowler, Leila R. Vale, Weijie Guo
We demonstrate photon counting at 1550~nm wavelength using microwave kinetic inductance detectors (MKIDs) made from TiN/Ti/TiN trilayer films with superconducting transition temperature $T_{c} \sim$ 1.4~K. The detector has a lump-element design with a

A practical superconducting-microcalorimeter X-ray spectrometer for beamline and laboratory science

May 16, 2017
Author(s)
William B. Doriese, Peter Abbamonte, Douglas A. Bennett, Edward V. Denison, Yizhi Fang, Daniel A. Fischer, Colin P. Fitzgerald, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Cherno Jaye, Jessica L. McChesney, Luis Miaja Avila, Kelsey M. Morgan, Young Il Joe, Galen C. O'Neil, Carl D. Reintsema, Fanny Rodolakis, Daniel R. Schmidt, Hideyuki Tatsuno, Jens Uhlig, Leila R. Vale, Joel N. Ullom, Daniel S. Swetz
We describe a series of microcalorimeter X-ray spectrometers designed for a broad suite of measurement applications. The chief advantage of this type of spectrometer is that it can be orders of magnitude more efficient at collecting X-rays than more

Beating Darwin-Bragg losses in lab-based ultrafast x-ray experiments

March 24, 2017
Author(s)
Wilfred Fullagar, Jens Uhlig, Ujjwal Mandal, Dharma Kurunthu, Amal El Nahhas, Hideyuki Tatsuno, Alireza Honarfar, Fredrik Gustafsson, Villy Sundstrom, Mikko Palosaari, Luis Miaja Avila, Young Il Joe, Daniel S. Swetz, Joel N. Ullom
The use of low temperature thermal detectors for avoiding Darwin-Bragg losses in lab-based ultrafast experiments has begun. An outline of the background of this new development is offered, showing the relevant history and initiative taken by this work.

Ultrafast time-resolved x-ray absorption spectroscopy of ferrioxalate photolysis with a laser plasma x-ray source and microcalorimeter array

February 17, 2017
Author(s)
Galen C. O'Neil, Joel N. Ullom, Luis Miaja Avila, Young Il Joe, Joseph W. Fowler, Carl D. Reintsema, Daniel S. Swetz, Kevin L. Silverman, Daniel R. Schmidt, Bruce D. Ravel, Gene C. Hilton, William B. Doriese, Bradley K. Alpert, Ralph Jimenez
Using a table-top apparatus based upon a laser plasma x-ray source and an array of cryogenic microcalorimeter x-ray detectors, we have measured the transient x-ray absorption spectrum during the ferrioxalate photoreduction reaction. We observe the Fe K

Compact 2.2 K Cooling System for Superconducting Nanowire Single Photon Detectors

January 25, 2017
Author(s)
Vincent Y. Kotsubo, Ray Radebaugh, Sae Woo Nam, Joel N. Ullom, Brandon L. Wilson, Paul Hendershott, Micheal Bonczyski
We are developing a compact, low power, closed cycle cooling system for Superconducting Nanowire Single Photon Detectors. The base temperature of the present prototype, which uses a helium-4 Joule-Thomson stage, is 2.2 K with over 1.2 mW of cooling. This

An Overhanging Absorber for TES X-ray Focal Planes

December 23, 2016
Author(s)
James P. Hays-Wehle, Peter J. Lowell, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
In order to improve pixel count and collecting area, future TES x-ray focal planes require pixels with both a higher coverage of the active area and compatibility with in-focal-plane multiplexing. We anticipate these improvements by developing a pixel with

When "Optimal Filtering" Isn't

December 8, 2016
Author(s)
Joseph W. Fowler, Bradley K. Alpert, William B. Doriese, James P. Hays-Wehle, Young Il Joe, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom, Daniel R. Schmidt, Daniel S. Swetz
The so-called ``optimal filter'' analysis of a microcalorimeter's x-ray pulses is statistically optimal only if all pulses have the same shape, regardless of energy. The shapes of pulses from a nonlinear detector can and do depend on the pulse energy

A Thin-Film Cryotron Suitable For Use as an Ultra-Low-Temperature Switch

October 6, 2016
Author(s)
Peter J. Lowell, John A. Mates, William B. Doriese, Gene C. Hilton, Kelsey M. Morgan, Daniel S. Swetz, Joel N. Ullom, Daniel R. Schmidt
Low-temperature superconducting circuits have become important in modern science. However, there are presently no high-current-capacity switches with low power dissipation for sub-Kelvin operation. One candidate for a sub-Kelvin switch is the cryotron, a

First application of superconducting transition-edge-sensor microcalorimeters to hadronic-atom x-ray spectroscopy

September 30, 2016
Author(s)
Douglas A. Bennett, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, James P. Hays-Wehle, Gene C. Hilton, Carl D. Reintsema, Daniel S. Swetz, Joel N. Ullom
High-resolution pionic-atom x-ray spectroscopy was performed with an x-ray spectrometer based on a 240-pixel array of superconducting transition-edge-sensor (TES)microcalorimeters at the πM1 beam line of the Paul Scherrer Institute. The pionic-carbon 4 → 3

Ultrafast time-resolved hard x-ray emission spectroscopy on a table top

September 27, 2016
Author(s)
Luis Miaja Avila, Galen C. O'Neil, Young Il Joe, Bradley K. Alpert, Niels Damrauer, William B. Doriese, Steven Fatur, Joseph W. Fowler, Gene C. Hilton, Ralph Jimenez, Carl D. Reintsema, Daniel R. Schmidt, Kevin L. Silverman, Daniel S. Swetz, Hideyuki Tatsuno, Joel N. Ullom
Chemical reactions driven by light are fundamental to biology and a source of inspiration for engineering materials to perform tasks such as solar energy harvesting and data storage. Observing and understanding photodynamics requires experimental tools

Code-division-multiplexed readout of large arrays of TES microcalorimeters

September 15, 2016
Author(s)
Kelsey M. Morgan, Bradley K. Alpert, Douglas A. Bennett, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kent D. Irwin, Young Il Joe, Galen C. O'Neil, Carl D. Reintsema, Edward V. Denison, Daniel R. Schmidt, Joel N. Ullom, Daniel S. Swetz
Code-division multiplexing (CDM) offers a path to reading out large arrays of transition edge sensor (TES) X-ray micro-calorimeters with excellent energy and timing resolution. We demonstrate the readout of X-ray TESs with a 32-channel flux-summed code

Design of 280 GHz feedhorn-coupled TES arrays for the balloon-borne polarimeter SPIDER

July 7, 2016
Author(s)
Johannes Hubmayr, Jason E. Austermann, James A. Beall, Daniel T. Becker, Shannon M. Duff, Arpi L. Grigorian, Gene C. Hilton, Joel N. Ullom, Michael R. Vissers
We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure large-scale B-mode polarization of the cosmic microwave back-ground (cmb) in search of the cosmic-inflation