Nav: Home

Accelerating quantum technologies with materials processing at the atomic scale

May 14, 2019

'Quantum technologies' utilise the unique phenomena of quantum superposition and entanglement to encode and process information, with potentially profound benefits to a wide range of information technologies from communications to sensing and computing.

However a major challenge in developing these technologies is that the quantum phenomena are very fragile, and only a handful of physical systems have been identified in which they survive long enough and are sufficiently controllable to be useful. Atomic defects in materials such as diamond are one such system, but a lack of techniques for fabricating and engineering crystal defects at the atomic scale has limited progress to date.

A team of scientists demonstrate, in a paper published in Optica, the success of the new method to create particular defects in diamonds known as nitrogen-vacancy (NV) colour centres. These comprise a nitrogen impurity in the diamond (carbon) lattice located adjacent to an empty lattice site or vacancy. The NV centres are created by focusing a sequence of ultrafast laser pulses into the diamond, the first of which has an energy high enough to generate vacancies at the centre of the laser focus, with subsequent pulses at a lower energy to mobilise the vacancies until one of them binds to a nitrogen impurity and forms the required complex.

The new research was carried out by a team led by Prof Jason Smith in the Department of Materials, University of Oxford, and Dr Patrick Salter and Prof Martin Booth in the Dept of Engineering Science, University of Oxford, in collaboration with colleagues at the University of Warwick. It took place within the research programme of NQIT, the Quantum Computing Technology Hub of the UK Quantum Technologies Programme, with support from DeBeers UK who supplied the diamond sample.

The scientists' new method involves a sensitive fluorescence monitor being employed to detect light emitted from the focal region, so that the process can be actively controlled in response to the observed signal. By combining local control and feedback, the new method facilitates the production of arrays of single NV centres with exactly one colour centre at each site - a key capability in building scalable technologies. It also allows precise positioning of the defects, important for the engineering of integrated devices. The rapid single-step process is easily automated with each NV centre taking only seconds to create.

Prof Martin Booth says: 'Colour centres in diamond offer a very exciting platform for developing compact and robust quantum technologies, and this new process is a potential game-changer in the engineering of the required materials. There is still more work to do in optimising the process, but hopefully this step will help to accelerate delivery of these technologies.'

The scientists believe that this method might ultimately be used to fabricate centimetre-sized diamond chips containing 100,000 or more NV centres as a route towards the 'holy grail' of quantum technologies, a universal fault-tolerant quantum computer.

Prof Jason Smith says: 'The first quantum computers are now starting to emerge but these machines, impressive as they are, only scratch the surface of what might be achieved and the platforms being used may not be sufficiently scalable to realise the full power that quantum computing has to offer. Diamond colour centres may provide a solution to this problem by packing high densities of qubits onto a solid state chip, which could be entangled with each other using optical methods to form the heart of a quantum computer. The ability to write NV centres into diamond with a high degree of control is an essential first step towards these and other devices.'
For more information or to request images, please contact the University of Oxford press office at / 01865 280730.

The paper is available here:

Notes to editors

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the third year running, and at the heart of this success is our ground-breaking research and innovation. Oxford is world-famous for research excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 170 new companies since 1988. Over a third of these companies have been created in the past three years.


NQIT, the UK quantum computing technology hub, is the largest of the four Hubs in the UK National Quantum Technologies Programme. NQIT is a consortium of nine universities and organisations, led by University of Oxford, working towards building a quantum computer demonstrator and creating a quantum computing sector in the UK.

University of Oxford

Related Quantum Computing Articles:

New method could enable more stable and scalable quantum computing, Penn physicists report
Researchers from the University of Pennsylvania, in collaboration with Johns Hopkins University and Goucher College, have discovered a new topological material which may enable fault-tolerant quantum computing.
Stanford team brings quantum computing closer to reality with new materials
Quantum computing could outsmart current computing for complex problem solving, but only if scientists figure out how to make it practical.
Computing -- quantum deep
In a first for deep learning, an Oak Ridge National Laboratory-led team is bringing together quantum, high-performance and neuromorphic computing architectures to address complex issues that, if resolved, could clear the way for more flexible, efficient technologies in intelligent computing.
Legacy of brilliant young scientist is a major leap in quantum computing
Researchers from the University of Bristol and Université Libre de Bruxelles have theoretically shown how to write programs for random circuitry in quantum computers.
WSU mathematician breaks down how to defend against quantum computing attacks
WSU mathematician Nathan Hamlin is the author of a new paper that explains how a code he wrote for a doctoral thesis, the Generalized Knapsack Code, could thwart hackers armed with next generation quantum computers.
Protecting quantum computing networks against hacking threats
As we saw during the 2016 US election, protecting traditional computer systems, which use zeros and ones, from hackers is not a perfect science.
Electron-photon small-talk could have big impact on quantum computing
In a step that brings silicon-based quantum computers closer to reality, researchers at Princeton University have built a device in which a single electron can pass its quantum information to a particle of light.
Bridging the advances in AI and quantum computing for drug discovery and longevity research
Insilico Medicine Inc. and YMK Photonics Inc. announced a research collaboration and business cooperation to develop photonics quantum computing and accelerated deep learning techniques for drug discovery, biomarker development and aging research.
New technique for creating NV-doped nanodiamonds may be boost for quantum computing
Researchers at North Carolina State University have developed a new technique for creating NV-doped single-crystal nanodiamonds, only four to eight nanometers wide, which could serve as components in room-temperature quantum computing technologies.
Exploring defects in nanoscale devices for possible quantum computing applications
Researchers at Tokyo Institute of Technology in collaboration with the University of Cambridge have studied the interaction between microwave fields and electronic defect states inside the oxide layer of field-effect transistors at cryogenic temperatures.

Related Quantum Computing Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".