Saturday, September 22, 2012

Australia: qubit as a single silicon atom

Peter F. has pointed out the following intriguing experimental advance in quantum computing:
Australians Create 1-Atom Silicon Quantum Computing Bit (quBit) (Daily Tech)
How does it work?

Well, they take an ordinary single silicon atom, rotate its electron spin (bound to a phosphorus donor atom) in the desired direction by a 1-tesla magnetic field, and then cool it (at least the electrons) down to 0.3 kelvins or so. They're able to manipulate with the electron spin by some clever microwave pulses.

The coherence time is a quarter of a millisecond so far which is pretty good but in their Nature paper,
A single-atom electron spin qubit in silicon,
they hope to get to a second by a tighter control over the phosphorous doping.

Equally optimistically, the electrodes etc. almost look like they are already preparing a commercial implementation of the technology. I believe that if the main element behind classical computers and artificial breasts is used, some if not many existing technologies may be be perhaps recycled to produce a working quantum computer for the first time.

Lazaridis goes into quantum computing

In this article about quantum computing, it may be sensible to point out that they're opening the Mike & Ophelia Lazaridis Quantum-Nano Centre at the University of Waterloo. Links: first, second, third. Hat tip: Joseph S.


  1. Cool!
    Probably it would take decades to develop that technology, but very nice progress.

  2. Wow ! Thanks for sharing.

  3. Dumb question: Besides rendering all the world's secret codes obsolete, what would be the practical advantage of a quantum computer?

  4. I'd say to guess/predict what will happen at short, medium and long term...

  5. Dear Luke, if you're not going to be excited by any of the algorithms on this page

    and consider them "practical", then the answer is clearly Nothing, but I would encourage you to consider the possibility that due to the method, such an outcome could be a bad grade for you rather than quantum computing.

  6. The thought came to me, that within ten years a Q-calculator might be made and ready to crunch! %-o