Another step forward for diamond-based quantum computers

Square cut or pear-shaped, these qubits don't lose their shape


Building simple quantum gates is common, but creating something that could be built on transistor-like scale is a huge challenge. Now, boffins from the Technical University of Vienna, Japan's National Institute of Informatics, and NTT's Basic Research Labs are offering an architecture they reckon can be scaled up.

What the researchers are offering, they believe, is a basic architecture they think would support a scalable quantum computer based on spins of nitrogen atoms in diamonds.

The architecture uses nitrogen atoms that can occupy two spin states, injected into a diamond, with each nitrogen defect trapped in a two-mirror optical resonator. Optical fibres let the engineers couple photons to this quantum system, allowing them to work with it without destroying the nitrogen atom spins.

As the researchers write in their paper at Physical Review X, “Modules are connected by photons propagating in a fiber-optical network. The cavities mediate interactions between the photons and the electron spins, enabling entanglement distribution and readout. The electron spins are coupled to nuclear spins, which constitute long-lived quantum memories where quantum information is stored and processed”.

Individual systems can then be connected together in an error-resistant two-dimensional array, the researchers say. Around 4.5 billion individual qubits would be required to run Shor's prime-factoring quantum computing algorithm on a 2048-bit prime, they add, but this architecture offers the potential for its individual elements to be miniaturised.

A quantum-diamond experimental chip at TU Vienna

TU Vienna is already experimenting with nitrogen-in-diamond quantum chips. Image: TU Vienna

TU Vienna's announcement is here.

Last year, UC Santa Barbara researchers demonstrated controlling a nitrogen vacancy centre in diamond using photons. ®

Similar topics

Broader topics


Other stories you might like

  • Protecting data now as the quantum era approaches
    Startup QuSecure is the latest vendor to jump into the field with its as-a-service offering

    Analysis Startup QuSecure will this week introduce a service aimed at addressing how to safeguard cybersecurity once quantum computing renders current public key encryption technologies vulnerable.

    It's unclear when quantum computers will easily crack classical crypto – estimates range from three to five years to never – but conventional wisdom is that now's the time to start preparing to ensure data remains encrypted.

    A growing list of established vendors like IBM and Google and smaller startups – Quantum Xchange and Quantinuum, among others – have worked on this for several years. QuSecure, which is launching this week after three years in stealth mode, will offer a fully managed service approach with QuProtect, which is designed to not only secure data now against conventional threats but also against future attacks from nation-states and bad actors leveraging quantum systems.

    Continue reading
  • D-Wave deploys first US-based Advantage quantum system
    For those that want to keep their data in the homeland

    Quantum computing outfit D-Wave Systems has announced availability of an Advantage quantum computer accessible via the cloud but physically located in the US, a key move for selling quantum services to American customers.

    D-Wave reported that the newly deployed system is the first of its Advantage line of quantum computers available via its Leap quantum cloud service that is physically located in the US, rather than operating out of D-Wave’s facilities in British Columbia.

    The new system is based at the University of Southern California, as part of the USC-Lockheed Martin Quantum Computing Center hosted at USC’s Information Sciences Institute, a factor that may encourage US organizations interested in evaluating quantum computing that are likely to want the assurance of accessing facilities based in the same country.

    Continue reading
  • BMW looks to quantum computers to speed R&D
    Pasqal to provide compute based on approaches by Qu&Co acquisition

    BMW has become the latest company to give quantum an early chance, with the goal of shrinking development cycles beyond traditional means.

    Quantum computing systems and software startup Pasqal announced that it is partnering with the German automaker, which will use the French biz's proprietary differential-equation-solving algorithm to test quantum computing's applicability to metal-forming modeling.

    BMW is experimenting with Pasqal's systems to reduce time spent building and testing physical models of metal components, which often have to be minutely tweaked after testing to achieve the results designers and engineers want.

    Continue reading

Biting the hand that feeds IT © 1998–2022