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Search Publications by: Dan Schmidt (Fed)

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Displaying 101 - 125 of 160

Phase-slip lines as a resistance mechanism in transition-edge sensors

January 27, 2014
Author(s)
Douglas A. Bennett, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The fundamental mechanism of resistance in voltage-biased superconducting films is poorly understood despite its importance as the basis of transition-edge sensors (TESs). TESs are utilized in state-of- the-art microbolometers and microcalorimeters

Identification and elimination of anomalous thermal decay in gamma-ray microcalorimeters

November 18, 2013
Author(s)
Robert D. Horansky, Douglas A. Bennett, Daniel R. Schmidt, Barry L. Zink, Joel N. Ullom
Microcalorimeter detectors rely on superconducting components and cryogenic temperatures to provide over an order-of-magnitude improvement in energy resolution compared to semiconducting sensors. Resolution improvements impact fields from gamma-ray

High resolution gamma-ray spectroscopy with a microwave-multiplexed TES array

November 11, 2013
Author(s)
Omid Noroozian, John A. Mates, Douglas A. Bennett, Justus A. Brevik, Joseph W. Fowler, Jiansong Gao, Robert D. Horansky, Kent D. Irwin, Daniel R. Schmidt, Joel N. Ullom, Zhao Kang
We demonstrate the first gamma-ray spectroscopy with a microwave-multiplexed two-pixel TES(transition-edge sensor) array. We measured a $^{153}$Gd photon source and achieved an energy resolution of 63 eV full-width-at-half-maximum (FWHM) at 97 keV and an

Vapor Phase Metal-assisted Chemical Etching of Silicon

March 14, 2013
Author(s)
Owen J. Hildreth, Daniel R. Schmidt
This work introduces and explores Vapor Phase Metal-assisted Chemical Etching (VP-MaCE) of silicon as a method to bypass some of the challenges found in traditional Liquid Phase Metal-assisted Chemical Etching (LP-MaCE). Average etch rates for Ag, Au, and

Current Distribution and Transition Width in Superconducting Transition-Edge Sensors

December 13, 2012
Author(s)
Daniel S. Swetz, Douglas A. Bennett, Daniel R. Schmidt, Joel N. Ullom
Present models of the superconducting-to-normal transition in transition-edge sensors (TESs)do not describe the current distribution within a biased TES. This distribution is complicated by normal-metal features that are integral to TES design. We present

Observation of bias-specific telegraph noise in large transition-edge sensors

December 11, 2012
Author(s)
Vincent Y. Kotsubo, Douglas A. Bennett, Mark Croce, Michael W. Rabin, Daniel R. Schmidt, Joel N. Ullom
We have observed anomalous random telegraph noise in discrete regions of voltage bias throughout the superconducting transition in larger transition-edge sensors (TESs). The bimodal nature of these noise features is consistent with thermally activated

A high resolution gamma-ray spectrometer based on superconducting microcalorimeters

September 28, 2012
Author(s)
Douglas A. Bennett, Robert D. Horansky, Daniel R. Schmidt, Andrew Hoover, Ryan Winkler, Bradley K. Alpert, James A. Beall, William B. Doriese, Joseph W. Fowler, Gene C. Hilton, Kent D. Irwin, Nathan J. Hoteling, Vincent Y. Kotsubo, John A. Mates, Galen C. O'Neil, Michael W. Rabin, Carl D. Reintsema, Francis J. Schima, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gammaray microcalorimeters, based on transition-edge sensors (TESs)

A two-fluid model for the transition shape in transition-edge sensors

May 1, 2012
Author(s)
Douglas A. Bennett, Daniel S. Swetz, Robert D. Horansky, Daniel R. Schmidt, Joel N. Ullom
Superconducting microcalorimeters based on transition-edge sensors (TESs) are being successfully used in applications ranging from optical photon counting to gamma-ray and alpha particle spectroscopy. Practical instruments often require a complex

Demonstration of code-division multiplexing for x-ray microcalorimeters

February 13, 2012
Author(s)
Greg Stiehl, W.Bertrand (Randy) Doriese, Gene C. Hilton, Kent D. Irwin, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila R. Vale, Joseph Fowler
We demonstrate the code-division multiplexing (CDM) readout of eight transition-edge sensor microcalorimeters. The energy resolution is 3.0 eV (full width at half-maximum) or better at 5.9 keV, with a best resolution of 2.3 eV and a mean of 2.6 eV over the

Advanced Code-Division Multiplexers for Superconducting Detector Arrays

February 11, 2012
Author(s)
Kent D. Irwin, Hsiao-Mei Cho, William B. Doriese, Joseph W. Fowler, Gene C. Hilton, Michael D. Niemack, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Leila R. Vale
Multiplexers based on the modulation of superconducting quantum interference devices are now regularly used in multi-kilopixel arrays of superconducting detectors for astrophysics, cosmology, and materials analysis. Over the next decade, much larger arrays

Optimization of the TES-bias circuit for a multiplexed microcalorimeter array

January 27, 2012
Author(s)
William B. Doriese, Bradley K. Alpert, Joseph W. Fowler, Gene C. Hilton, Alex S. Hojem, Kent D. Irwin, Carl D. Reintsema, Daniel R. Schmidt, Greg Stiehl, Daniel S. Swetz, Joel N. Ullom, Leila R. Vale
In the detector-bias circuit of a transition-edge-sensor (TES) microcalorimeter, the TES-shunt resistor (Rsh) and the thermal conductance to the cryogenic bath (G) are often considered to be interchangeable knobs with which to control detector speed

Optimization and analysis of code-division multiplexed TES microcalorimeters

January 20, 2012
Author(s)
Joseph W. Fowler, William B. Doriese, Gene C. Hilton, Kent D. Irwin, Daniel R. Schmidt, Greg Stiehl, Daniel S. Swetz, Joel N. Ullom, Leila R. Vale
We are developing code-division multiplexing (CDM) readout systems for TES arrays for good scalability to large multiplexing factors. We report high energy resolution x-ray measurements made through four-channel CDM that employ a flux-summing architecture