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Search Publications by: Anna Fox (Fed)

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Displaying 1 - 25 of 57

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

Demonstration of Superconducting Optoelectronic Single-Photon Synapses

October 6, 2022
Author(s)
Saeed Khan, Bryce Primavera, Jeff Chiles, Adam McCaughan, Sonia Buckley, Alexander Tait, Adriana Lita, John Biesecker, Anna Fox, David Olaya, Richard Mirin, Sae Woo Nam, Jeff Shainline
Superconducting optoelectronic hardware is being explored as a path towards artificial spiking neural networks with unprecedented scales of complexity and computational ability. Such hardware combines integrated-photonic components for few-photon, light

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

Measurement Challenges for Scaling Superconductor-based Quantum Computers

June 23, 2022
Author(s)
Pete Hopkins, Manuel Castellanos Beltran, John Biesecker, Paul Dresselhaus, Anna Fox, Logan Howe, David Olaya, Adam Sirois, Dylan Williams, Samuel P. Benz, Alirio De Jesus Soares Boaventura, Justus Brevik
Global investment in the research and development of quantum information systems by industry, government, and academic institutions continues to accelerate and is expected to reach over $16B by 2027 [1]. Systems based on optical photons, atoms or ions

Bipolar Waveform Synthesis with an Optically Driven Josephson Arbitrary Waveform Synthesizer

April 19, 2022
Author(s)
Justus Brevik, Dahyeon Lee, Anna Fox, Yiwei Peng, Akim Babenko, Joe Campbell, Paul Dresselhaus, Franklyn Quinlan, Samuel P. Benz
An array of Josephson junctions (JJs) was driven with photonically generated current pulses to synthesize a high-fidelity 1 kHz bipolar voltage waveform with a quantum-based amplitude that can be directly related to fundamental constants. A photodiode

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

Josephson Microwave Sources Applied to Quantum Information Systems

December 18, 2020
Author(s)
Adam J. Sirois, Manuel C. Castellanos Beltran, Anna E. Fox, Samuel P. Benz, Peter F. Hopkins
Quantum computers with thousands or millions of qubits will require a scalable solution for qubit control and readout electronics. Colocating these electronics at millikelvin temperatures has been proposed and demonstrated, but there exist significant

Cryogenic Calibration of a Quantum-based Radio Frequency Source

November 2, 2020
Author(s)
Alirio De Jesus Soares Boaventura, Justus A. Brevik, Dylan Williams, Anna E. Fox, Manuel C. Castellanos Beltran, Peter F. Hopkins, Paul D. Dresselhaus, Samuel P. Benz
We report on the calibration of quantum-based radio frequency waveforms generated by a Josephson arbitrary waveform synthesizer system. We measure these waveforms using a vector network analyzer and calibrate them at 4 K using a custom-designed cryogenic

Cryogenic Calibration of a Quantum-based Radio Frequency Source

November 2, 2020
Author(s)
Alirio De Jesus Soares Boaventura, Justus Brevik, Dylan Williams, Anna Fox, Manuel Castellanos Beltran, Pete Hopkins, Paul Dresselhaus, Samuel P. Benz
We report on the calibration of quantum-based radio frequency waveforms generated by a Josephson arbitrary waveform synthesizer system. We measure these waveforms using a vector network analyzer and calibrate them at 4 K using a custom-designed cryogenic

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

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

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

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

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