SRI 6011 series Page 1 of 4

National Institute of Standards & Technology

Specifications

Standard Reference Instrument Series 6011

Josephson Arbitrary Waveform Synthesizer

Description: The Josephson arbitrary waveform synthesizer (JAWS) is an instrument that 

synthesizes ac voltage waveforms and dc voltages whose metrological accuracy results from pulse 

biasing thousands of series-connected superconducting Josephson junctions into their identical 

quantum states. The quantum accuracy of these voltages is derived from the Josephson Effect, 

such that every junction in the JAWS circuit produces the integer number and polarity of quantized 

voltage pulses at precisely determined time.

The JAWS system is essentially a digital-to-analog converter that generates time-dependent 

voltage signals that serve as a primary ac voltage standard. It is the only ac voltage standard source 

directly derived from quantum effects. Waveforms such as sine waves or arbitrary waveforms may 

be synthesized with frequencies and harmonics ranging from four hertz to a few megahertz 

frequencies. As a result of circuit and output lead impedances, the accuracy of the waveforms 

provided to test instruments will depend on the frequency, with lower audio frequencies having 

the lowest uncertainty. For example, a 1 kHz, 1 V rms sine wave has an uncertainty (k=1) of one 

part in 107, whereas a 100 kHz sine wave will have an uncertainty (k=1) of one part in 105 at the 

output leads. The uncertainty is limited by ac leakage paths and is expected to decrease as more 

advanced measurement techniques are refined. System software characterizes and accounts for 

the largest of these errors. Contributions to the uncertainty include extrinsic effects such as 

transmission line errors, and quadrature errors from the compensation currents, as well as intrinsic 

errors from the delta-sigma code and phase noise. A detailed study is available on request.

Design, assembly and technical measurements leading to the production of this SRI were 

performed by P.D. Dresselhaus of the NIST Quantum Electromagnetics Division.

Support aspects involved in the issuance of this SRI were coordinated through the NIST Office of 

Reference Materials.

Paul D. Hale, Chief

RF Technology Division

Steven J. Choquette, Director

Gaithersburg, MD 20899 Office of Reference Materials 

Certificate Issue Date: 03 February 2022 Material Measurement Laboratory
SRI 6011 series Page 2 of 4 

Specifications: NIST provides the JAWS as Standard Reference Instrumentation (SRI) with 

performance that is equivalent to that of NIST systems in terms of quantum accuracy and precision 

measurement capability, provided that operators follow recommended best practices and perform 

intercomparisons with comparable quantum-based voltage sources. The NIST JAWS SRI is 

offered in a range of different configurations (SRI 6011a – SRI 6011c), from individual 1V JAWS 

cryo-packaged chips that contain the superconducting integrated circuit to fully integrated JAWS 

systems in which the chip is cooled by a cryocooler refrigerator to the operating temperature at 

which the JAWS circuit becomes superconducting. The JAWS chips are fabricated and packaged 

by NIST in accordance with existing and established fabrication protocols. All the system 

configurations of the JAWS SRI are constructed primarily from commercially available 

components and include software that optimizes the system performance and ensures that it 

produces quantum-accurate waveforms. 

NIST researchers continue to develop and improve the JAWS systems and measurement 

techniques. The JAWS circuits and systems and associated measurement capabilities are identical 

to those of NIST systems at the time of acquisition. NIST is providing the JAWS through the SRI 

program with prices derived such that NIST is reimbursed for all costs associated with duplicating 

the current versions of NIST systems. Prices do not include support, training, warranty, or on-site 

installation and qualification. The customer should contact the Standard Reference Instrument 

office (srminfo@nist.gov) for costs for these services.

The JAWS circuits and systems have the following specifications and features.1

A) A cryopackaged chip that is tested and demonstrated to produce stable, quantum-accurate 

waveforms at up to 1 V rms or 2 V rms with a minimum current range of 1.0 mA that is 

determined by a Total Harmonic Distortion better than -100 dBc. 

B) The capability to generate voltage waveforms with frequency components from 4 Hz up 

to 1 MHz. 

C) A majority of system components that are commercially available.

a. Fast pulse synthesizer operating at >12 Gpulses/s with at least two (2) 

independent channels 

b. Low-frequency function generators for bias and triggering 

c. Wideband RF amplifiers with 30 dB gain, >30 GHz bandwidth, and >8 Vpp 

output 

d. Low-noise digitizer with >50 MSa/s and >16-bit per sample for analysis and 

margins testing

e. Optically isolated low-frequency amplifiers

D) Patterns will use a pulse frequency of >12 Giga-pulses/sec with user-defined waveforms 

or a standard set of NIST-generated waveforms for standard voltages and frequencies: 

0.1, 0.2, 0.5, 0.75, and 1 V rms at 100 Hz, 200 Hz, 500 Hz, 1 kHz, 2 kHz, 5 kHz, 10 kHz, 

20 kHz, 50 kHz, and 100 kHz. Combined uncertainties (k=2) in parts in 106

 (220 mV 

range at 200 mV output voltage) are: 

1 Certain commercial equipment, instruments or materials are identified in this certificate to adequately specify the 

experimental procedure. Such identification does not imply recommendation or endorsement by the National Institute of Standards 

and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
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100 Hz 400 Hz 1 kHz 2 kHz 5 kHz 10 kHz 20 kHz

2 2 2 2 2 4 12

from “Uncertainty Analysis for the Army Primary Standards Laboratory”, J. Underwood, 

2017. 

E) Electronic and hardware integration components, cables, wrenches, and equipment rack. 

F) A single-node license of the JAWS system software that automatically evaluates and 

optimizes the performance of the chip and the system electronics in order to ensure that 

the voltages are quantum accurate and have the largest current range.

G) Application software that provides ac-dc difference measurements and calibrations of 

various voltage sources and meters 

Delivery: Delivery and installation dates will be determined on a case-by-case basis in 

coordination with the customer and based on the availability of components and NIST staff. 

Shipping: Unless otherwise agreed by the parties, shipping terms shall be EXW (Incoterms 

2010). NIST will prepare packaging for shipment of the JAWS SRI. Shipping crate dimensions 

and weight will be included in each quote. Customers are responsible for arrangement of 

shipping pickup at NIST as well as all customs duties and import fees (HTC 9030.33.0040). 

Technical requirements at installation site: Customers must provide the following: 

A) A 10 MHz reference signal whose frequency is accurate to a part in 10^10 or better. 

B) A Windows-based computer system (Windows 10 or higher) with at least 16 GB of RAM 

for data analysis and system operation. At least four (4) USB-2 ports are required. 

C) Customs related clearances, documents, payments, and fees.

D) Appropriate power and utilities for compressors (for cryo-cooled systems only), 

including power and connectors for three-phase 208 V, 6 kW at 60 Hz (or three-phase 

200 V, 5 kW at 50 Hz) power, and cooling water (for the water-cooled compressor only). 

E) Providing, as the customer deems necessary, the following additional instruments that are 

typically used for calibration measurements and are currently support by existing JAWS 

software:

a. A Fluke 792A thermal transfer standard

b. A Fluke 5790 ac voltmeter for rms voltage measurement 

F) Liquid helium (for liquid-helium-cooled systems only) for both the on-site qualification 

as well as for daily operation. 

Users of this SRI should ensure that the Specifications Certificate in their possession is current. This can be 

accomplished by contacting the Office of Reference Materials: telephone (301) 975-2200; e-mail srminfo@nist.gov; 

or via the Internet at http://www.nist.gov/sri.
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Josephson Arbitrary Waveform Synthesizer (JAWS) System Configurations

SRI 6011 series

6011a Cryo-cooled 1V rms JAWS, with water-cooled compressor

a. Fast pulse synthesizer operating at >12 Gpulses/s with at least two (2) independent channels

b. Low-frequency function generators for bias and triggering

c. Wideband RF amplifiers with 30 dB gain, >30 GHz bandwidth, and >8 Vpp output

d. Optically isolated low-frequency amplifiers

e. Cryocooler with >400 mW cooling power at 4 K and water-cooled compressor

f. Cryo-packaged 1V rms JAWS chip

g. Low-noise digitizer with >50 MSa/s and >16-bit per sample

h. NIST JAWS software

6011b Cryo-cooled 1V rms JAWS, with air-cooled compressor

a. Fast pulse synthesizer operating at >12 Gpulses/s with at least two (2) independent channels

b. Low-frequency function generators for bias and triggering

c. Wideband RF amplifiers with 30 dB gain, >30 GHz bandwidth, and >8 Vpp output

d. Optically isolated low-frequency amplifiers

e. Cryocooler with >400 mW cooling power at 4 K and air-cooled compressor

f. Cryo-packaged 1V rms JAWS chip

g. Low-noise digitizer with >50 MSa/s and >16-bit per sample

h. NIST JAWS software

6011c Cryo-packaged 1V rms JAWS chip (standalone)

6011d Cryo-packaged 2V rms JAWS chip (standalone)

6011e 1V JAWS Cryo-package with Liquid Helium Cryoprobe

6011f Cryocooled 2V JAWS System, with water-cooled compressor

a. Fast pulse synthesizer operating at >12 Gpulses/s with at least two (2) independent channels

b. Low-frequency function generators for bias and triggering

c. Wideband RF amplifiers with 30 dB gain, >30 GHz bandwidth, and >8 Vpp output

d. Optically isolated low-frequency amplifiers

e. Cryocooler with >400 mW cooling power at 4 K and water-cooled compressor

f. Cryo-packaged 2V rms JAWS chip

g. Low-noise digitizer with >50 MSa/s and >16-bit per sample

h. NIST JAWS software

6011g Cryocooled 2V JAWS System, with water-cooled compressor, no synthesizer

a. Low-frequency function generators for bias and triggering

b. Wideband RF amplifiers with 30 dB gain, >30 GHz bandwidth, and >8 Vpp output

c. Optically isolated low-frequency amplifiers

d. Cryocooler with >400 mW cooling power at 4 K and water-cooled compressor

e. Cryo-packaged 2V rms JAWS chip

f. Low-noise digitizer with >50 MSa/s and >16-bit per sample

g. NIST JAWS software