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Search Publications by: Nathan Flowers-Jacobs (Fed)

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Displaying 1 - 25 of 35

Practical realisation of the kelvin by Johnson noise thermometry

February 15, 2024
Author(s)
Horst Rogalla, D Rod White, Jifeng Qu, Samuel P. Benz, Christof Gaiser, Weston L. Tew, Nathan Flowers-Jacobs, Kevin J. Coakley, Alessio Polarollo, Chiharu Urano
Johnson noise thermometry (JNT) is a purely electronic method of thermodynamic thermometry. In primary JNT, the temperature is inferred from a comparison of the Johnson noise voltage of a resistor at the unknown temperature with a pseudo-random noise

Sub-GHz Resolution Line-by-Line Pulse Shaper for Driving Josephson Junctions

August 29, 2023
Author(s)
Dahyeon Lee, Takuma Nakamura, Andrew Metcalf, Nathan Flowers-Jacobs, Anna Fox, Paul Dresselhaus, Franklyn Quinlan
We demonstrate a sub-GHz resolution, fully programmable Fourier-domain pulse shaper capable of generating arbitrary optical pulse patterns. This high resolution allows line-by-line pulse shaping of a 1 GHz comb with a span as large as 1 THz, which

Quantum-Based Microwave Modulated Waveforms

August 4, 2023
Author(s)
Akim Babenko, Nathan Flowers-Jacobs, Anna Fox, Paul Dresselhaus, Zoya Popovic, Samuel P. Benz
This paper presents a superconducting voltage source that generates microwave modulated waveforms with quantum-based stability. The voltage source - an RF Josephson Arbitrary Waveform Synthesizer (RF-JAWS) - uses a superconducting IC with an array of 4500

Cryogenic Decade-Passband Superconducting Integrated Diplexer

August 29, 2022
Author(s)
Akim Babenko, GREGOR LASSER, Nathan Flowers-Jacobs, Justus Brevik, Anna Fox, ZOYA POPOVIC, Paul Dresselhaus
We demonstrate a decade-passband superconducting diplexer operating from dc to 27 GHz, integrated in a niobium, Josephson-junction(JJ)-compatible process. Both low- and high-pass branches are singly-terminated 5-pole Butter-worth filters with a 2.5 GHz

RF Josephson Arbitrary Waveform Synthesizer with Integrated Superconducting Diplexers

August 24, 2022
Author(s)
Akim Babenko, Nathan Flowers-Jacobs, GREGOR LASSER, Justus Brevik, Anna Fox, Paul Dresselhaus, Zoya Popovic, Samuel P. Benz
We present the design, fabrication and characterization of a broadband RF Josephson Arbitrary Waveform Synthesizer (RF-JAWS) with a series array of 4500 Josephson junctions (JJs) and integrated low-pass/high-pass five-pole superconducting diplexers. The

Cryogenic Characterization of a Superconductor Quantum-Based Microwave Reference Source for Communications and Quantum Information

October 13, 2021
Author(s)
Alirio De Jesus Soares Boaventura, Justus Brevik, Dylan Williams, Nathan Flowers-Jacobs, Manuel Castellanos Beltran, Anna Fox, Pete Hopkins, Paul Dresselhaus, Samuel P. Benz
We are developing a new instrument, the RF Josephson arbitrary waveform synthesizer (RF-JAWS), for communications metrology and quantum information applications. An important aspect of the RF-JAWS design is the accurate and traceable characterization of

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

October 22, 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 80 kHz by using the DJIB to compare the best available impedance standards that are (a) directly traceable to the quantum Hall effect, (b) used as

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

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

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

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

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

Characterization of a Dual Josephson Impedance Bridge

October 21, 2018
Author(s)
Nathan Flowers-Jacobs, Blaise Jeanneret, Frederic Overney, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel P. Benz
This paper describes a dual Josephson impedance bridge capable of comparing any two impedances, that is, with any amplitude ratio and relative phase, over a wide range of frequency. A new, more compact, design has been achieved by mounting the two

DC Comparison of a Programmable Josephson Voltage Standard and a Josephson Arbitrary Waveform Synthesizer

July 7, 2018
Author(s)
Alain Rufenacht, Nathan Flowers-Jacobs, Anna Fox, Steven B. Waltman, Robert E. Schwall, Paul Dresselhaus, Samuel P. Benz, Charles J. Burroughs
We present the first dc comparison of a programmable Josephson voltage standards and a pulse- driven Josephson arbitrary waveform synthesizer (JAWS) at 3 V. Both devices are mounted side- by-side on the cold stage of a cryocooler. The relative agreement

Radiofrequency Waveform Synthesis with the Josephson Arbitrary Waveform Synthesizer

July 7, 2018
Author(s)
Justus Brevik, Christine A. Donnelly, Nathan Flowers-Jacobs, Anna Fox, Pete Hopkins, Paul Dresselhaus, Samuel P. Benz
We have measured the frequency-dependent voltage output up to 100 MHz of a modified version of the Josephson Arbitrary Waveform Synthesizer. An impedance-matching resistor was integrated within the Josephson junction array circuit to match the nominally

Three Volt Pulse-Driven Josephson Arbitrary Waveform Synthesizer

July 7, 2018
Author(s)
Nathan Flowers-Jacobs, Alain Rufenacht, Anna Fox, Steven B. Waltman, Justus Brevik, Paul Dresselhaus, Samuel P. Benz
This paper describes a new generation of Josephson Arbitrary Waveform Synthesizers which generate ac waveforms with a root-mean-squared (rms) amplitude of 3 V over a quantum-accurate operating range greater than 1 mA at 1 kHz. This system is composed of