U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by:

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 1 - 25 of 32

Single-Flux-Quantum Multiplier Circuits for Synthesizing Gigahertz Waveforms With Quantum-Based Accuracy

February 3, 2021
Author(s)
Manuel C. Castellanos Beltran, David I. Olaya, Adam J. Sirois, Christine A. Donnelly, Paul Dresselhaus, Samuel Benz, Peter F. Hopkins
We designed, simulated, and experimentally demonstrated components for a microwave frequency digital-to-analog converter (DAC) based on rapid single flux quantum (RSFQ) circuits and a superconducting amplifier based on SQUID stacks. These are key

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

Synaptic weighting in single flux quantum neuromorphic computing

January 22, 2020
Author(s)
Michael L. Schneider, Christine A. Donnelly, Ian W. Haygood, Alex Wynn, Stephen E. Russek, Manuel C. Castellanos Beltran, Paul D. Dresselhaus, Peter F. Hopkins, Matthew R. Pufall, William H. Rippard
Josephson junctions act as a natural spiking neuron-like device for neuromorphic computing. By leveraging the advances recently demonstrated in digital single flux quantum (SFQ) circuits and using recently demonstrated magnetic Josephson junction (MJJ)

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

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

Energy efficient single flux quantum based neuromorphic computing

November 8, 2018
Author(s)
Michael Schneider, Christine A. Donnelly, Stephen E. Russek, Burm Baek, Matthew Pufall, Pete Hopkins, William Rippard
Many neuromorphic hardware technologies are being explored for their potential to increase the efficiency of computing certain problems, and thus facilitate machine learning with greater energy efficiency and or with more complexity. Among the technologies

Jitter Sensitivity Analysis of the Superconducting Josephson Arbitrary Waveform Synthesizer

November 4, 2018
Author(s)
Christine A. Donnelly, Justus Brevik, Paul Dresselhaus, Pete 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

High-speed low-power neuromorphic systems based on magnetic Josephson junctions

October 25, 2018
Author(s)
Michael Schneider, Christine A. Donnelly, Stephen E. Russek
Josephson junctions and single flux quantum (SFQ) circuits form a natural neuromorphic technology with SFQ pulses and superconducting transmission lines simulating action potentials and axons, respectively. Josephson junctions consist of superconducting

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

Superconducting optoelectronic networks III: synaptic plasticity

July 5, 2018
Author(s)
Jeffrey M. Shainline, Adam N. McCaughan, Sonia M. Buckley, Christine A. Donnelly, Manuel C. Castellanos Beltran, Michael L. Schneider, Richard P. Mirin, Sae Woo Nam
As a means of dynamically reconfiguring the synaptic weight of a superconducting optoelectronic loop neuron, a superconducting flux storage loop is inductively coupled to the synaptic current bias of the neuron. A standard flux memory cell is used to

Superconducting optoelectronic networks II: receiver circuits

April 6, 2018
Author(s)
Jeffrey M. Shainline, Sonia M. Buckley, Adam N. McCaughan, Manuel C. Castellanos Beltran, Christine A. Donnelly, Michael L. Schneider, Richard P. Mirin, Sae Woo Nam
Circuits using superconducting single-photon detectors and Josephson junctions to perform signal reception, synaptic weighting, and integration are investigated. The circuits convert photon-detection events into flux quanta, the number of which is
Was this page helpful?