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Search Publications by: Samuel P. Benz (Fed)

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Displaying 26 - 50 of 286

Characterization of a Josephson Junction Comb Generator

October 13, 2020
Author(s)
Akim Babenko, Alirio De Jesus Soares Boaventura, Nathan Flowers-Jacobs, Justus Brevik, Anna Fox, Dylan Williams, Zoya Popovic, Paul Dresselhaus, Samuel P. Benz
We present a new type of microwave frequency combs with a potentially calculable pulse shape. The device is an array of 1500 Josephson junctions (JJs) connected in series along a transmission line. The pulse generation is based on the nonlinearity of the

A Cryogenic Quantum-Based RF Source

September 10, 2020
Author(s)
Justus A. Brevik, Alirio De Jesus Soares Boaventura, Manuel C. Castellanos Beltran, Christine A. Donnelly, Nathan E. Flowers-Jacobs, Anna E. Fox, Peter F. Hopkins, Paul D. Dresselhaus, Dylan Williams, Samuel P. Benz
We performed a preliminary calibrated measurement of the output power of a Josephson arbitrary waveform synthesizer up to 1 GHz. We present the results and measurement procedure for generating quantum-based signals using an array of Josephson junctions

Direct DC Voltages Comparison between two Programmable Josephson Voltage Standards at SCL

September 10, 2020
Author(s)
S. Yang, Stefan Cular, Alain Rufenacht, Charles J. Burroughs, Paul Dresselhaus, Samuel Benz, M. N. Ng
Standards and Calibration Laboratory (SCL) setup in 2018 a liquid helium based programmable Josephson voltage standard (PJVS) developed by the National Institute of Standards and Technology (NIST). The system was validated by direct comparison with a NIST

Calibration of an AC Voltage Source Using a Josephson Arbitrary Waveform Synthesizer at 4 V

August 24, 2020
Author(s)
Nathan E. Flowers-Jacobs, Alain Rufenacht, Anna E. Fox, Paul D. Dresselhaus, Samuel P. Benz
This paper describes a method for calibrating an ac source using a Josephson Arbitrary Waveform Synthesizer (JAWS) by summing the sources in series and tuning the magnitude and phase of the JAWS to null the combined output voltage. The method requires an

Compact DC Josephson Voltage Standard

August 24, 2020
Author(s)
Alain Rufenacht, Anna E. Fox, Grace E. Butler, Charles J. Burroughs, Paul D. Dresselhaus, Robert E. Schwall, Stefan Cular, Samuel P. Benz
This paper presents precision measurements with a prototype cryogen-liquid-free DC Josephson voltage standard that produces a 1 V maximum output. Its cryostat is sufficiently compact that it can be operated on a bench close to devices under test. Compared

Zero-Compensation Josephson Arbitrary Waveform Synthesizer at 1.33 V

August 24, 2020
Author(s)
Nathan E. Flowers-Jacobs, Akim Babenko, Anna E. Fox, Justus A. Brevik, Paul D. Dresselhaus, Samuel P. Benz
This paper describes the generation of a quantum-based rms output voltage of 1.332 V using an ac-coupled Josephson Arbitrary Waveform Synthesizer (JAWS) without any low-frequency compensation current biases, that is, in a 'zero-compensation' (ZC) mode. Low

Dual Josephson impedance bridge: towards a universal bridge for impedance metrology

May 19, 2020
Author(s)
Frederic Overney, Nathan Flowers-Jacobs, Blaise Jeanneret, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
This paper presents a full characterization of a Dual Josephson Impedance Bridge (DJIB) at frequencies up to 80kHz by using the DJIB to compare the best available impedance standards that are (a) directly traceable to the quantum Hall effect, (b) used as

Development and Applications of a Four-Volt Josephson Arbitrary Waveform Synthesizer

February 13, 2020
Author(s)
Nathan E. Flowers-Jacobs, Alain Rufenacht, Anna E. Fox, Steven B. Waltman, Robert E. Schwall, Justus A. Brevik, Paul D. Dresselhaus, Samuel P. Benz
We have recently created a 4 V rms cryocooled JAWS (Josephson Arbitrary Waveform Synthesizer) using 204,960 nearly identical Josephson junctions (JJs) that are embedded in coplanar-wave guides. The JJs are pulse-biased at repetition rates up to 16 × 10 9

Microwave Modeling and Characterization of Superconductive Circuits for Quantum Voltage Standard Applications at 4 Kelvin

February 10, 2020
Author(s)
Alirio De Jesus Soares Boaventura, Dylan F. Williams, Richard A. Chamberlin, Jerome G. Cheron, Anna E. Fox, Paul D. Dresselhaus, Peter F. Hopkins, Ian W. Haygood, Samuel P. Benz
We developed a cryogenic multiline thru-reflect-line (TRL) calibration kit for microwave characterizing of superconductive circuits used in the Josephson arbitrary waveform synthesizer of the national institute of standards and technology (NIST). We also

Johnson Noise Thermometry

September 3, 2019
Author(s)
Weston L. Tew, Jifeng Qu, K L. Zhou, Samuel P. Benz, Horst Rogalla, David R. White
Johnson noise thermometers infer thermodynamic temperature from measurements of the thermally-induced current fluctuations that occur in all electrical conductors. This paper reviews the status of Johnson noise thermometry and its prospects for both

Josephson Junctions for Metrology Applications

August 30, 2019
Author(s)
Samuel P. Benz
The Josephson effect has revolutionized voltage metrology [1-5] and, together with the quantum Hall effect for resistance and atomic clocks for time and frequency, has enabled measurement standards based on quantum effects. Quantum standards produce

1 GHz Waveform Synthesis with Josephson Arrays

July 31, 2019
Author(s)
Christine A. Donnelly, Justus A. Brevik, Nathan E. Flowers-Jacobs, Peter F. Hopkins, Paul D. Dresselhaus, Samuel P. Benz
For the first time, we synthesize single- and multiple-tone waveforms at gigahertz frequencies from arrays of Josephson junctions and demonstrate quantum-locked operation over a range of experimental input parameters. We first use a lumped-element circuit

1 GHz Waveform Synthesis With Josephson Junction Arrays

July 31, 2019
Author(s)
Christine A. Donnelly, Nathan E. Flowers-Jacobs, Justus A. Brevik, Anna E. Fox, Paul D. Dresselhaus, Peter F. Hopkins, Samuel P. Benz
We synthesize single- and multiple-tone waveforms at gigahertz frequencies from arrays of Josephson junctions and demonstrate their quantum-locked operation over a range of experimental input parameters. We first use a lumped-element circuit to synthesize

Pulse-Driven High-Tc Josephson Junctions for Quantum Voltage Devices

July 28, 2019
Author(s)
Adam C. Weis, Nathan E. Flowers-Jacobs, E Y. Choi, H Li, J C. LeFebvre, Shane Cybart, Stuart Berkowitz, Horst Rogalla, Samuel P. Benz
Josephson junction arrays are the basis for quantum-accurate dc and ac voltage standards, including artificial voltage-noise references used in noise thermometry. I will describe our recent progress towards voltage synthesis using high-transition

Quantized Pulse Propagation in Josephson Junction Arrays

July 23, 2019
Author(s)
Christine A. Donnelly, Justus Brevik, Nathan Flowers-Jacobs, Anna Fox, Paul Dresselhaus, Peter F. Hopkins, Samuel Benz
We present time-domain electrical measurements and simulations of the quantized voltage pulses that are generated from series-connected Josephson junction (JJ) arrays. The transmission delay of the JJ array can lead to a broadening of the net output pulse

Induced Current Effects in Josephson Voltage Standard Circuits

March 8, 2019
Author(s)
Anna E. Fox, Grace E. Butler, Miranda L. Thompson, Paul D. Dresselhaus, Samuel P. Benz
A study has been performed to understand the effects of magnetic field induced current in Josephson voltage standard circuits. Inductive filtering is an essential component in Josephson voltage standard devices for isolation of the microwave and DC bias

Planarized process for single-flux-quantum circuits with self-shunted Nb/NbxSi1-x/Nb Josephson junctions

February 18, 2019
Author(s)
David I. Olaya, Manuel C. Castellanos Beltran, Javier Pulecio, John P. Biesecker, Soroush Khadem, Theodore Lewitt, Peter F. Hopkins, Paul D. Dresselhaus, Samuel P. Benz
We describe the single-flux-quantum (SFQ) circuit fabrication process employed at NIST's Boulder Microfabrication Facility. The process includes four superconducting metal layers, one palladium-gold resistor layer, and a contact pad layer. Chemical

RF waveform synthesizers with quantum-based voltage accuracy for communications metrology

February 11, 2019
Author(s)
Peter F. Hopkins, Justus A. Brevik, Manuel C. Castellanos Beltran, Nathan E. Flowers-Jacobs, Anna E. Fox, David I. Olaya, Christine A. Donnelly, Paul D. Dresselhaus, Samuel P. Benz
We report on NIST’s development of Josephson junction-based programmable reference sources to synthesize quantum-accurate, spectrally-pure waveforms for characterizing and improving next generation communication devices and systems. The goal is to provide

Stacked Josephson Junctions as inductors for SFQ circuits

February 11, 2019
Author(s)
Manuel C. Castellanos Beltran, David I. Olaya, Adam J. Sirois, Paul D. Dresselhaus, Samuel P. Benz, Peter F. Hopkins
In order for Single Flux Quantum (SFQ) circuits to be scaled to densities needed for large-scale integration, typical lithographically-patterned circuit components should be made to be as compact as possible. In this work, we characterize the performance

Jitter Sensitivity Analysis for Pulsed-Output RF Superconducting Digital to Analog Converters

November 5, 2018
Author(s)
Christine A. Donnelly, Justus A. Brevik, Paul D. Dresselhaus, Peter F. Hopkins, Samuel P. Benz
We present the first jitter sensitivity analysis of a superconducting voltage reference waveform synthesizer with fundamentally accurate output pulses. Successful deployment of a reference waveform source at microwave frequencies will represent a new