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Search Publications by: Joel Ullom (Fed)

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Displaying 276 - 300 of 352

A TDMA Hybrid SQUID Multiplexer

January 25, 2008
Author(s)
Carl D. Reintsema, James A. Beall, W.Bertrand (Randy) Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Dan Schmidt, Joel Ullom, Leila R. Vale, Yizi Xu
We have developed a multiplexed read-out for transition edge sensors based on a hybrid time- and frequency-domain basis set, similar to that used in time-division multiple-access (TDMA) mobile phones. The hybrid basis set uses bandwidth more efficiently

Large array of multiplexed gamma-ray microcalorimeters for nuclear-materials analysis

January 24, 2008
Author(s)
W.Bertrand (Randy) Doriese, Joel Ullom, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, John Mates, Carl D. Reintsema, Dan Schmidt, Leila R. Vale, Yizi Xu, Barry L. Zink, Michael W. Rabin, Minesh K. Bacrania, Stephen Lamont, Andrew Hoover, Clifford R. Rudy, Duc Vo, C. K. Stahle, Kevin R. Boyce, Larry E. Brown, Jonathan M. King, F. S. Porter
We are developing a gamma-ray spectrometer for the analysis of nuclear materials based on an array of superconducting transition-edge-sensor microcalorimeters. The instrument includes eight columns of time-division-SQUID multiplexing circuitry capable of

Materials Analysis with Cryogenic Sensors

January 24, 2008
Author(s)
Joel N. Ullom
Low temperature photon detectors are increasingly attractive tools for materials analysis. Their range of applications has broadened from early work on x-ray fluorescence and now spans the electromagnetic spectrum from terahertz to gamma-ray energies. In

Operation of an X-ray transition-edge sensor cooled by tunnel junction refrigerators

January 19, 2008
Author(s)
Nathan A. Tomlin, James A. Beall, Gene C. Hilton, Kent D. Irwin, Galen O'Neil, Dan Schmidt, Leila R. Vale, Joel Ullom
We demonstrate successful cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal/insulator/superconductor (NIS) tunnel junctions. Above the TES transition temperature (Tc), we use Johnson noise thermometry to

Multiplexed microcalorimeter arrays for precision measurements from microwave to gamma-ray wavelengths

August 21, 2007
Author(s)
Joel Ullom, W.Bertrand (Randy) Doriese, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, Terrence J. Jach, John Mates, Nathan A. Tomlin, Galen O'Neil, Carl D. Reintsema, Nicholas Ritchie, Dan Schmidt, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Clifford R. Rudy, Derek Tournear, Duc Vo, Michael W. Rabin
Cryogenic microcalorimeters are a promising technology for ultrasensitive measurements of electromagnetic radiation from microwave to gamma-ray wavelengths. Cryogenic microcalorimeters derive their exquisite sensitivity from the minimal thermal noise at

A 14-pixel, multiplexed array of gamma-ray microcalorimeters with 47 eV energy resolution at 103 keV

May 9, 2007
Author(s)
W.Bertrand (Randy) Doriese, Joel Ullom, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, John Mates, Carl D. Reintsema, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Michael W. Rabin, Clifford R. Rudy, Duc Vo
We present a prototype for a high-energy-resolution, high-count-rate, gamma-ray spectrometer intended for nuclear forensics and international nuclear safeguards. The prototype spectrometer is an array of 14 transition-edge-sensor microcalorimeters with an

Demonstration and modeling of an array-compatible TES microcalorimeter gamma-ray detector with 42 eV energy resolution at 103 keV

September 20, 2006
Author(s)
Barry L. Zink, Joel Ullom, James A. Beall, Kent D. Irwin, W.Bertrand (Randy) Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Carl D. Reintsema, Leila R. Vale
We describe a microcalorimeter gamma-ray detector with measured energy resolution of 42 eV full width at half maximum for 103 keV photons. This detector consists of a thermally isolated superconducting transition-edge thermometer and a superconducting bulk

Erbium-doped Gold Sensor Films for Magnetic Microcalorimeter X-ray Detectors*

April 17, 2006
Author(s)
Barry L. Zink, Kent D. Irwin, Gene C. Hilton, Joel Ullom, David P. Pappas
We briefly review the principles of a magnetic microcalorimeter x-ray detector and the requirements for fabricating an array of these sensors, which include a paramagnetic sensor fabricated with thin-film techniques. We discuss two methods for depositing

Normal Metal-insulator-superconductor Junction Technology for Bolometers

April 15, 2006
Author(s)
Dan Schmidt, William Duncan, Kent D. Irwin, Konrad Lehnert, Nathan A. Tomlin, Joel Ullom
Normal metal-insulator-superconductor tunnel junctions are candidates for large-format arrays of ultra-low noise equivalent power bolometers. Using a wafer scale process we have fabricated devices with required the sub $\mu}$m$^3}$ volumes and ohmic

Optimization of Transition-Edge Calorimeter Performance

April 15, 2006
Author(s)
Joel N. Ullom, James A. Beall, William B. Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Galen C. O'Neil, Carl D. Reintsema, Leila R. Vale, Barry L. Zink
Calorimeters that exploit the superconducting-to-normal transition are used to detect individual photons from near-infrared to γ-ray wavelengths. Across this wide range, absorption efficiency, speed, and energy resolution are key performance parameters

Microwave SQUID multiplexers for low-temperature detectors

January 10, 2006
Author(s)
Kent D. Irwin, James A. Beall, W.Bertrand (Randy) Doriese, William Duncan, Gene C. Hilton, John Mates, Carl D. Reintsema, Dan Schmidt, Joel Ullom, Leila R. Vale, Barry L. Zink, Konrad Lehnert
We report on the development of a SQUID multiplexer operated at microwave frequencies. This multiplexer can accommodate any detector that can be read out with SQUIDs, including transition-edge sensors, magnetic calorimeters, and superconductor-insulator

Toward kilopixel arrays: 3.8 eV microcalorimeter resolution in 8-channel SQUIDmultiplexer

January 10, 2006
Author(s)
W.Bertrand (Randy) Doriese, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Carl D. Reintsema, Joel Ullom, Leila R. Vale, Yizi Xu
Over the past several years, NIST has developed a SQUID time-division multiplexer (TDM) to read out large arrays of transition-edge sensors (TESs). The NIST TDM architecture has been successful in a number of submillimeterand millimeter-wave applications

Development of a solid-state 100 mK refrigerator for user-supplied microelectronics

January 4, 2006
Author(s)
Nathan A. Tomlin, William Duncan, James A. Beall, Gene C. Hilton, Kent D. Irwin, Dan Schmidt, Joel Ullom
Solid-state refrigerators based on normal metal/insulator/superconductor tunnel junctions are now a practical means of cooling from pumped 3He bath temperatures to near 100 mK. While integration of NIS refrigerators with transition-edge sensors is underway