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Search Publications by: Samuel P. Benz (Fed)

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Displaying 51 - 75 of 276

Automated Direct Comparison of Two Cryocooled 10 Volt Programmable Josephson Voltage Standards

July 6, 2018
Author(s)
Alain Rufenacht, Yi-hua D. Tang, Stephane Solve, Anna E. Fox, Paul D. Dresselhaus, Charles J. Burroughs, Robert E. Schwall, Regis Chayramy, Samuel P. Benz
We have performed direct dc comparisons between two cryocooled 10 V programmable Josephson voltage standards utilizing an automated synchronization scheme for the voltage reversals, which enables the use of a high-sensitivity analog null detector on its 10

The Boltzmann Project

February 5, 2018
Author(s)
Samuel P. Benz, Joachim Fischer, Bernd Fellmuth, Christof Gaiser, Laurent Pitre, Fernando Sparasci, Lara Risegari, Roberto M. Gavioso, D M. Rippa, Bengt Hallstedt, Jifeng Qu, XiaoJuan Feng, Jianqiang Zhang, David R. White, L Gianfrani, A Castrillo, L Moretti, B Darquie, C Daussy, S Briaudeau, O Kozlova, J J. Segovia, M C. Martin, D del Campo, Michael R. Moldover
The International Committee for Weights and Measures (CIPM), at its meeting in October 2017 followed the recommendation of the Consultative Committee for Units (CCU) on the redefinition of the kilogram, ampere, kelvin and mole. For the redefinition of the

Ultralow power artificial synapses using nanotextured magnetic Josephson junctions

January 28, 2018
Author(s)
Michael L. Schneider, Christine A. Donnelly, Stephen E. Russek, Burm Baek, Matthew R. Pufall, Peter F. Hopkins, Paul D. Dresselhaus, Samuel P. Benz, William H. Rippard
Neuromorphic computing is a promising avenue to dramatically improve the efficiency of certain computational tasks, such as perception and decision making. Neuromorphic systems are currently being developed for critical applications ranging from self

The NIST Johnson noise thermometry system for the determination of the Boltzmann constant

December 29, 2017
Author(s)
Nathan Flowers-Jacobs, Alessio Pollarolo, Kevin Coakley, Adam C. Weis, Anna Fox, Horst Rogalla, Weston L. Tew, Samuel Benz
In preparation for the redefinition of the International System of Units (SI), five different electronic measurements of the Boltzmann constant have been performed using different Johnson noise thermometry (JNT) systems over the past seven years. In this

A Boltzmann Constant Determination Based on Johnson Noise Thermometry

August 10, 2017
Author(s)
Nathan E. Flowers-Jacobs, Alessio Pollarolo, Kevin J. Coakley, Anna E. Fox, Horst Rogalla, Weston L. Tew, Samuel P. Benz
A value for the Boltzmann constant was measured electronically using an improved version of the Johnson Noise Thermometry (JNT) system at the National Institute of Standards and Technology (NIST), USA. This system is different from prior ones, including

An improved electronic measurement of the Boltzmann constant by Johnson noise thermometry

July 18, 2017
Author(s)
Jifeng Qu, Samuel Benz, Kevin Coakley, Horst Rogalla, Weston L. Tew, David R. White, Kunli Zhou, Zhenyu Zhou
Recent measurements using acoustic gas thermometry have determined the value of the Boltzmann constant, k, with a relative uncertainty less than 110-6. These results have been supported by a measurement with a relative uncertainty of 1.910-6 made with

Fabrication of High-Speed and High-Density Single-Flux-Quantum Circuits at NIST

June 11, 2017
Author(s)
David Olaya, Paul Dresselhaus, Pete Hopkins, Samuel P. Benz
The development of a fabrication process for single-flux-quantum (SFQ) digital circuits is a fundamental part of the NIST effort to develop a gigahertz waveform synthesizer with quantum voltage accuracy. This paper describes the current SFQ fabrication

Scalable, High-Speed, Digital Single-Flux-Quantum Circuits at NIST

June 11, 2017
Author(s)
Pete Hopkins, Manuel Castellanos Beltran, Christine A. Donnelly, Paul Dresselhaus, David Olaya, Adam Sirois, Samuel P. Benz
We describe NIST's capabilities for designing and fabricating niobium-based single-flux quantum (SFQ) digital and mixed-signal circuits and show test results of our first circuits. We have assembled a package of software design tools that are readily

Advanced Waveform Synthesis with Pulse-driven Josephson Voltage Standards

February 21, 2017
Author(s)
Justus A. Brevik, Nathan E. Flowers-Jacobs, Anna E. Fox, Evan B. Golden, Paul D. Dresselhaus, Samuel P. Benz
We describe the implementation of new commercial pulse-bias electronics that have enabled an improvement in the generation of quantum-accurate waveforms both with and without low-frequency compensation biases. We have used these electronics to apply a

On-Chip Temperature Distribution for Josephson Voltage Standards

November 22, 2016
Author(s)
Anna E. Fox, Evan B. Golden, Paul D. Dresselhaus, Samuel P. Benz
A substrate surface temperature characterization for the National Institute of Standards and technology Josephson voltage standard has been performed by fabricating and measuring Josephson junction arrays with on-chip thermometry. Circuits were designed

Stochastic Single Flux Quantum Neuromorphic Computing using Magnetically Tunable Josephson Junctions

October 16, 2016
Author(s)
Stephen E. Russek, Christine A. Donnelly, Michael Schneider, Burm Baek, Matthew Pufall, William Rippard, Pete Hopkins, Paul Dresselhaus, Samuel P. Benz
Abstract— Single flux quantum (SFQ) circuits form a natural neuromorphic technology with SFQ pulses and superconducting transmission lines simulating action potentials and axons, respectively. Here we present a new component, magnetic Josephson junctions

2 V Pulse-Driven Josephson Arbitrary Waveform Synthesizer

July 10, 2016
Author(s)
Nathan E. Flowers-Jacobs, Alain Rufenacht, Anna E. Fox, Paul D. Dresselhaus, Samuel P. Benz
We created a Josephson Arbitrary Waveform Synthesizer (JAWS) with a root-mean-square (rms) output magnitude of 2 V. This system is composed of two 1 V chips operating on a cryocooler. By controlling the relative phase of the two chips’ output voltage, we

10 Volt Automated Direct Comparison of Two Cryocooled Programmable Josephson Voltage Standards

July 9, 2016
Author(s)
Alain Rufenacht, Yi-hua D. Tang, Paul Dresselhaus, Charles J. Burroughs, Robert E. Schwall, Samuel P. Benz
We have performed direct dc comparisons between two cryocooled 10 V programmable Josephson voltage standards utilizing an automated synchronization scheme for the voltage reversals, which enables the use of a high sensitivity null detector on its 3 µV

Direct comparison of a Pulse-driven Josephson Arbitrary Waveform Synthesizer and a Programmable Josephson Voltage Standard at 1 Volt

July 9, 2016
Author(s)
Alain Rufenacht, Nathan Flowers-Jacobs, Anna Fox, Charles J. Burroughs, Paul Dresselhaus, Samuel P. Benz
We have performed direct ac comparisons between two types of quantum voltage standards, a pulse- driven Josephson arbitrary waveform synthesizer and a programmable Josephson voltage standard, at 1 V rms amplitude and a frequency of 100 Hz. The system

Improved spectra aberration in the Johnson Noise Thermometry

July 9, 2016
Author(s)
Alessio Pollarolo, Horst Rogalla, Anna Fox, Kevin J. Coakley, Weston L. Tew, Samuel P. Benz
SPECTRAL ABERRATION HAS BEEN FOR A LONG TIME THE MAIN SOURCE OF UNCERTAINTY IN THE JOHNSON NOISE THERMOMETRY APPROACH TO MEASURING THE BOLTZMANN CONSTANT. RECENTLY, WITH NEWLY DEVELOPED HARDWARE AND THE INTRODUCTION OF A NOVEL FITTING ALGORITHM FOR

Josephson-Based Full Digital Bridge for High-Accuracy Impedance Comparisons

July 9, 2016
Author(s)
Frederic Overney, Nathan Flowers-Jacobs, Blaise Jeanneret, Alain Rufenacht, Anna Fox, Jason Underwood, Andrew D. Koffman, Samuel P. Benz
This paper describes a Josephson-based impedance bridge capable of comparing any types of impedance over a large bandwidth. The heart of the bridge is a dual AC Josephson Voltage Standards (ACJVS) source which offers unprecedented flexibility in high

Simultaneous Double Waveform Synthesis with a Single Programmable Josephson Voltage Standard

July 9, 2016
Author(s)
Alain Rufenacht, Anna Fox, Paul Dresselhaus, Charles J. Burroughs, Samuel P. Benz, Bryan C. Waltrip, Thomas L. Nelson
We have recently demonstrated new 2 V PJVS devices configured with two voltage outputs and two sets of least significant bits in order to simultaneously generate two independent stepwise output waveforms. This development improves upon our previous

Josephson-Based Full Digital Bridge for High-Accuracy Impedance Comparisons

June 24, 2016
Author(s)
Frederic Overney, Nathan Flowers-Jacobs, Blaise Jeanneret, Alain Rufenacht, Anna Fox, Jason Underwood, Andrew D. Koffman, Samuel P. Benz
This paper describes a Josephson-based full digital impedance bridge capable of comparing any two impedances, regardless of type (R-C, R-L, or L-C), over a large frequency range. At the heart of the bridge are two Josephson arbitrary waveform synthesizer

Two Volt Josephson Arbitrary Waveform Synthesizer Using Wilkinson Dividers

February 19, 2016
Author(s)
Nathan E. Flowers-Jacobs, Anna E. Fox, Paul D. Dresselhaus, Robert E. Schwall, Samuel P. Benz
The root-mean-square (rms) output voltage of the NIST Josephson arbitrary waveform synthesizer (JAWS) has been doubled from 1 V to a record 2 V by combining two new 1 V chips on a cryocooler. This higher voltage will improve calibrations of ac thermal

Voltage Metrology Using a Quantum AC Standard

September 1, 2015
Author(s)
Thomas E. Lipe, Joseph R. Kinard Jr., Yi-hua Tang, Samuel P. Benz, Charles J. Burroughs, Paul D. Dresselhaus
We report on the use of a quantum-based AC voltage standard for ac-dc difference metrology at the National Institute of Standards and Technology (NIST). The paper describes the characterization of the output transmission line, and the methods used to

Improved electronic measurement of the Boltzmann constant by Johnson noise Thermometry

August 19, 2015
Author(s)
Weston L. Tew, Samuel P. Benz, Horst Rogalla, Alessio Pollarolo, David R. White, Jifeng Qu, Kunli Zhou
The unit of thermodynamic temperature, the kelvin, will be redefined in 2018 by fixing the value of the Boltzmann constant, k. The present CODATA recommended value of k is determined predominantly by acoustic gas-thermometry results. To provide a value of