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Updated: May 16, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Digital-to-analog converter using a superconducting quantum interference device.
1Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, AIST Central-3, 1-1, Umezono, Tsukuba, Ibaraki 305-8563, Japan. m.nakanishi@aist.go.jp
The Review of Scientific Instruments
|December 5, 2012
Summary
We created a novel digital-to-analog converter (DAC) utilizing a superconducting quantum interference device (SQUID) for highly linear current output. This quantum-accurate device offers millions of adjustable current values with exceptional short-term stability.
Area of Science:
- Quantum electronics
- Superconducting devices
- Metrology
Background:
- Achieving high linearity in digital-to-analog converters (DACs) is crucial for precision measurements.
- Traditional DACs face limitations in linearity and resolution.
- Superconducting Quantum Interference Devices (SQUIDs) offer unique quantum properties exploitable for electronic applications.
Purpose of the Study:
- To develop a novel DAC with a current output.
- To leverage the quantum properties of a SQUID for enhanced linearity.
- To demonstrate the performance and potential applications of a SQUID-based DAC.
Main Methods:
- Development of a DAC incorporating a radio-frequency SQUID (rf-SQUID).
- Utilizing the periodic flux-dependent response of the SQUID for linearity.
- Experimental verification of the SQUID's periodicity and DAC's output characteristics.
Main Results:
- The SQUID DAC exhibits essentially linear output due to quantum accuracy.
- Output current is adjustable to ~100,000 to ~1,000,000 values depending on maximum output.
- Demonstrated short-term fluctuation of ~0.15 ppm, attributed to SQUID flux resolution.
- Successfully demonstrated voltage linearity measurements of a digital multimeter.
Conclusions:
- A SQUID-based DAC offers superior linearity and resolution compared to conventional converters.
- The device's quantum nature ensures high accuracy and stability.
- Potential applications in precision instrumentation and metrology are highlighted.
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