

Qubit survives record 39 minutes at room temperature - parondea
http://www.cbc.ca/news/technology/qubit-record-moves-quantum-computing-forward-1.2426986?cmp=rss

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Osmium
This is really exciting! For those not familiar, 180s (edit: as previously
published[2]) is a phenomenal amount of time at room temperature and it seems
they've beaten that now too. I was just looking for this recently in another
comment thread[1] too when talking about the really cool things you can do
when you have access to ultra-pure silicon-28 (which has been made as a result
of something that sounds quite boring–making a more accurate standard for the
kg–and is now having some exciting side benefits). Direct link to paper is
here[2]; I think it's open access.

I was lucky enough to see a talk by one of the authors recently and was left
very impressed. Quantum computing is probably the 'sexiest' application of
ultra-pure silicon-28 but there are so many others besides, including being
able to use ultra-fine optical transitions to identify defect complexes within
the silicon (arrangements of impurity atoms that can influence the properties
of silicon-based devices). If I remember rightly, there were several defects
that had been misidentified for years based on entirely reasonable
Occam's-razor like reasoning that have now been correctly identified thanks to
this work.

[1]
[http://news.ycombinator.com/item?id=6617183](http://news.ycombinator.com/item?id=6617183)

[2]
[http://www.sciencemag.org/content/336/6086/1280.full.pdf](http://www.sciencemag.org/content/336/6086/1280.full.pdf)

~~~
rexreed
That's 1800s.. a factor of 10 more!

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r2
Silicon never ceases to amaze me. While much of the research in solid state
physics these days is around novel materials like graphene, silicon continues
to dominate solid-state applications including all conventional computer
processors and most solar cells and will prove incredibly hard to unseat in
these areas. Now it appears to be a leading contender for quantum computing
platforms. It's an earth-abundant material with billions of research dollars
poured into it to support computing, so seeing progress in silicon quantum
computing means real hope for applications.

~~~
Osmium
Yes, very true, but this is in part because silicon is simply understood so
well now. Trust me when I say we could do just as exciting things and more
besides with other materials if we just understood them half as well!

To illustrate what I mean, consider the fact that the Czochralski process [1]
_exists_ and that it means you can get huge, pure, relatively defect-free
_ingots_ of silicon (see [2]). With new materials, we're happy just to grow a
few microns of the stuff, let alone something like that.

So you're right, silicon really is very incredible :) but we've reached the
point now that the new innovations are in part possible by sheer momentum
alone, like the billions of dollars of investment you mention. The big
challenge is to develop new materials that initially (possibly for decades or
more) are inferior to silicon but might ultimately unseat it. The only problem
is that no one really knows what that material will be in advance. A lot of
people right now are gambling on graphene, and from the amount of investment
alone something interesting should come from it, but who knows if there's
something else better out there just waiting for the attention it needs.

[1]
[http://en.wikipedia.org/wiki/Czochralski_process](http://en.wikipedia.org/wiki/Czochralski_process)
[2]
[http://en.wikipedia.org/wiki/File:Monokristalines_Silizium_f...](http://en.wikipedia.org/wiki/File:Monokristalines_Silizium_für_die_Waferherstellung.jpg)

~~~
alokv28
Not that I disagree with what you wrote, I just want to point out that silicon
dioxide is probably the most important reason silicon has reached such
ubiquity in electronics. No other material has a native oxide as good as SiO2,
even though the semiconductors themselves have superior properties than
silicon.

~~~
chid
The interface isn't good though.

~~~
levlandau
the interface is not too shabby

------
LukeWalsh
Publications from the lab:
[http://www.sfu.ca/physics/thewaltlab/publications.html](http://www.sfu.ca/physics/thewaltlab/publications.html)

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davorak
Thats great! I need to read the paper but if that is the life time of the
physical qubit then it is much larger then what is typically considered needed
for using quantum error correction to make logical qubits.

Logical qubits are made up of many physical qubits, with relatively short life
times, to make one logical qubits with an infinite life time. The longer life
time of logical qubits makes it considerably easier to perform long
calculations and store information.

If anyone knows how easily quantum error correction can be applied to this
system I would be interested in finding out.

~~~
chid
In theory, that amount of time should allow for error correction (assuming
there are more qubits to work with). The critical factor for computation is
this dephasing time divided by the gate operation time (how long it takes to
modify the qubit) which should be on the order of at least 10^5.

Single qubit operations have been shown to be on the order of 10's of
microseconds for P nuclear spins in Si. (Unfortunately behind paywall,
[http://www.nature.com/nature/journal/v496/n7445/full/nature1...](http://www.nature.com/nature/journal/v496/n7445/full/nature12011.html))

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typon
This is actually super legit, published in Science. Very exciting. I'm so
proud that Canada is a world leader in quantum computing research, what with
Waterloo and all the millions in funding they're spending at IQC. I hope this
is the first step in achieving real quantum computers.

~~~
jeffandersen
Except this took place at SFU.

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nly
1 minute longer than the theoretical maximum period for which you can sustain
an artificial wormhole

~~~
kristopolous
Is this in fiction or fact? If fact, can you provide some reference?

~~~
ngpio
It's fiction.[1] "Artificial wormholes cannot be sustained for more than 38
minutes under normal conditions."[2]

[1] Quite enjoyable fiction. My canonically chronological SG viewing order for
maximum enjoyment is available at
[https://docs.google.com/spreadsheet/pub?key=0AkwxWLA63pAmdG5...](https://docs.google.com/spreadsheet/pub?key=0AkwxWLA63pAmdG5jS0F1UkJBQW5vYXBZdl85VHN5dHc&output=html)

[2]
[http://stargate.wikia.com/wiki/Wormhole_physics](http://stargate.wikia.com/wiki/Wormhole_physics)

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Aardwolf
39 minutes? Hmm, still not good enough for long-term backup of your qubits :)

~~~
tzs
Doesn't the no cloning theorem mean that you cannot back up a qubit regardless
of how stable it is?

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JohnDoe365
For just too often claims like that could not been proved by others. Did they
release sufficient information that their experiment could be approved by
others?

