[ExI] Quantum Computers

[Anders Sandberg]

On 2013-11-15 18:37, John Clark wrote:
> Perhaps the biggest problem in making a quantum computer is overcoming 
> quantum decoherence. In yesterday's issue of the journal  Science 
> Kamyar Saeedi and his team reported that they placed phosphorous atoms 
> in a silicon matrix in a state of quantum coherence for over 3 hours 
> at liquid helium temperatures. And even at room temperature they 
> remained in quantum coherence for 39 minutes, at room temperature the 
> previous record was 2 seconds.  They think they might be able to do 
> even better, and possibly much better, if they use selenium instead of 
> phosphorous next time.

It is pretty impressive, indeed. Of course, nuclear spins are much more 
stable than particle spins and naturally isolated from each other.

By the way, I read the news story on my way back home in Oxford - just 
when I was passing outside the building where the group works. Nice 
coincidence... or is it? :-)

(phone reception is always bad in that area. I assume the signals get 
eaten by escaped quantum states, or something)

-- 
Dr Anders Sandberg
Future of Humanity Institute
Oxford Martin School
Oxford University