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Search Publications by: Anna Fox (Fed)

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Displaying 1 - 25 of 66

VHF Josephson Arbitrary Waveform Synthesizer

October 1, 2024
Author(s)
Jeremy Thomas, Nathan Flowers-Jacobs, Anna Fox, Akim Babenko, Samuel Benz, Paul Dresselhaus
We report on the design, fabrication, and measurement of a Very High Frequency band Josephson Arbitrary Waveform Synthesizer (VHF-JAWS) at frequencies up to 50.05 MHz. The VHF-JAWS chip is composed of a series array of 12810 Josephson junctions (JJs)

Differential Measurements of an AC Source with a Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Alain Rufenacht, Raegan Johnson, Anna Fox, Nathan Flowers-Jacobs, Charlie Burroughs, Samuel Benz, Paul Dresselhaus, STEPHANE SOLVE, Jesus Mejia
This paper describes differential sampling measurements of an ac source and a Josephson arbitrary waveform synthesizer (JAWS). A new iterative approach for aligning the phases of the JAWS and the source waveforms was implemented to minimize the

Digitizer Linearity Measurement with a Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Jesus Mejia, Alain Rufenacht, Raegan Johnson, Anna Fox, Nathan Flowers-Jacobs, Samuel Benz, Paul Dresselhaus
This article examines the non-linearity and gain error of a commercial digitizer on the 100 mV range with a Josephson Arbitrary Waveform Synthesizer (JAWS) as a reference. Different digitizer input filter settings were studied, and the shortest aperture of

Dual-Frequency-Bias Programmable Josephson Voltage Standard Circuit Design

August 30, 2024
Author(s)
Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
This paper presents a new 2 V programmable Josephson voltage standard circuit with dual microwave frequency input. This design provides three main features: (1) output voltages with nanovolt resolution, (2) the ability to perform a microwave frequency self

Measuring VHF Detector Linearity using a Quantum-Based Source

August 30, 2024
Author(s)
Jeremy Thomas, Nathan Flowers-Jacobs, Anna Fox, Alain Rufenacht, Paul Dresselhaus
We demonstrate the use of a Josephson Arbitrary Waveform Synthesizer (JAWS) for linearity measurements of two instruments: an RF power sensor and a fast ADC. The VHF-JAWS source consists of a chip with 12,810Josephson junctions located in a cryocooler and

Pulse Patterns for the Josephson Arbitrary Waveform Synthesizer

August 30, 2024
Author(s)
Nathan Flowers-Jacobs, Raegan Johnson, Jeremy Thomas, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
Δ-sigma algorithms are used to determine the desired sequence of quantum-based voltage pulses used by the Josephson Arbitrary Waveform Synthesizer (JAWS) to create calculable voltage waveforms. We describe typical settings used for synthesizing JAWS audio

Stability Study of ac Voltage Source using Josephson Voltage Standards

August 30, 2024
Author(s)
Ghislain Granger, Waldemar G. Kuerten Ihlenfeld, Alain Rufenacht, Nathan Flowers-Jacobs, Anna Fox, Raegan Johnson, Jesus Mejia
The stability of an ac voltage source fabricated at the National Research Council Canada (NRC) is investigated. NRC uses differential sampling to monitor the source voltage with respect to a step-wise approximated reference waveform generated by the

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

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