Quantum Computing

Quantum computers have the potential to address challenges of much greater complexity than what today's computers can solve, helping achieve advancements in science, technology, medicine, and more. This all begins with creating and initializing qubits, or quantum bits. Yokogawa offers a highly stable, low noise current source to create the magnetic field required in quantum computing to initialize these extremely sensitive qubits.

Quantum qubits are built up from Josephson junctions which, when integrated in a closed loop, are highly sensitive to small changes in the external magnetic field passing through the loop​. The magnetic field must be finely tuned so the quantized energy levels can be smoothly transformed, a crucial part of initializing a quantum computer.

GS200 - Yokogawa's Quantum Computing Solution

Current is applied through a wire from a DC current source to produce the magnetic field to initialize the qubits. Yokogawa's GS200 is a low voltage/current DC source with high accuracy, high stability, and high resolution, making for an ideal DC current source. With its excellent traceability, stability, and 5 1/2-digit resolution, the GS200 generates extremely low-noise DC voltage and current signals that are required for many applications. Additionally, the optional monitoring feature turns the GS200 into a voltage and current measuring instrument.

Learn more about the GS200.

Key Features

Low Noise

  • 100 uVp-p (10 V range, DC to 10 kHz)​
  • 3 uAp-p (100 mA range, DC to 10 kHz)

Noise waveform example at 0 V output in 10 V output range (observed using a 1000 times amplifier with a 10 kHz band-limiting filter)

High Stability

  • +/- 0.001% of setting + 20 uV (at 10 V range for one day)​
  • +/- 0.004% of setting + 3 uA (at 100 mA range for one day)​
  • The stability is specified out to 90 days

Example of 1 hour stability in output 200 mA range (as reference data)



To realize working Josephson junction-based qubits requires a current source with low noise and high accuracy, stability and resolution.  Click below to learn how the Yokogawa GS200 Precision DC Voltage / Current Source fulfils these requirements for the experimental quantum computing setups of Princeton University’s Dr Andras Gyenis.


Source measure units combine the best features of power supplies and digital multimeters and have numerous applications ranging from battery simulators, semiconductor characterization, and efficiency testing on power electronics. 


A new type of computer based on the theory of quantum mechanics, a quantum computer, is currently in development by researchers around the globe. The theory of quantum mechanics describes nature at the atomic and subatomic level. Quantum technology has the potential to build powerful tools that process information using the properties of atoms, photons, and electrons. These quantum computers could also address challenges of much greater complexity than what today's computers can solve, and help further advancements in science, technology, medicine, and more.

With countries spending billions of dollars, the race for who can produce the first practical, commercialized quantum computer is on. There are currently several approaches to build this sort of computer, and this all begins with creating and initializing quantum bits, also known as qubits.


The extreme test requirements of our research called for an OSA with extended MIR spectrum bandwidth capabilities up to 5μm, but we couldn’t find one on the market capable of measuring optical inputs at these wavelengths. Yokogawa Test&Measurement rose to the challenge and developed a new OSA model for us that would. Not only do we now have an instrument that is practically custom-made for our needs, it provides repeatable, accurate, and trusted measurement outputs and is easy to learn and use. Their equipment and ability to create a new optical measurement solution has definitely increased the overall efficiency and productivity of our research team.

— Martin Bernier, PhD, P.Eng., Full Professor, Centre de Optique, Photonique, et Laser, Université Laval

Product Overviews


    Introducing the new Yokogawa Test&Measurement AQ6380 Optical Spectrum Analyzer. This new OSA includes many sought-after features including:

    • An unprecedented 5 pm wavelength resolution
    • ±5 pm wavelength accuracy
    • 1200 nm to 1650 nm wavelength range
    • 65 dB wide close-in dynamic range
    • 80 dB stray light suppression
    • Automated wavelength calibration
    • Gas purging
    • DUT-oriented interface and test apps
    • Backward-compatible remote interface
    • 10.4in intuitive touchscreen
    • Up to 20x faster measurement
    • Remote operation capabilities


    From visible light to telecommunication bands and even up to applications in the 2000nm region, optical testing professionals count on the Yokogawa Test&Measurement optical testing family of products. For decades, these precision-based optical measuring instruments have met and exceeded the needs of many customers’ experimental requirements. Applicable to a range of uses in R&D, manufacturing, and academia, Yokogawa Test&Measurement OSAs, OTDRs, OWMs, modular manufacturing test systems, and more deliver quality, consistency, ease of use, and market leadership for all manner of optical test applications.




    Mastering the fundamentals of optical wavelength measurements and having a solid understanding of measurement principles for optical sources and devices is key to measuring with confidence. This webinar provides a thorough review of these foundational elements and concepts as well as:

    • Fiber identification and recommendations for routine care
    • Measurement techniques for different optical measurement devices
    • Example wavelength-specific applications for visible light to over 3000 nm such as telecommunications, biomedical, and atmospheric gas sensing
    • Important considerations for selecting an optical spectrum analyzer

    There are countless technologies available for optical communications devices and systems validation. With so many specifics to take into consideration, it's not always easy for an engineer to determine the best networking and fiber optic measurement solution to address their measurement needs.

    Key discussions in this on-demand webinar include:

    • The what, why, and how of available options like optical spectrum analyzers, optical wavelength meters, optical power meters, variable attenuators, fixed and tunable laser sources, and more
    • How to improve the quality and value of results for both active and passive optical devices
    • Ways to streamline productivity and reduce costs while also achieving higher data transmission rates, longer-distance transmissions, immunity to EMI, lower signal loss, lower latency, enhanced security, and improved energy efficiency
    • Trends driven by applications such as AI, quantum, and inter-satellite laser communications (i.e., space lasers!)

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