A correspondent writes to me about a recent article in the APS News describingThe Top Ten Physics Stories of 2008 and notes a very troubling sentence:
Diamond Detectors
Work on the molecular structure of carbon continues to show great promise for quantum computing. This year scientists were able to construct a nano-scale light source that emits a single photon at a time. The team first removed a solitary atom from the carbon's otherwise regular matrix and then introduced a nitrogen atom nearby. When they excited this crystal with a laser, single polarized photons were emitted from the empty space. These photons could be used to detect very small magnetic forces. Additionally the photons emitted contained two spin states and were able to exist in that state for nearly a millisecond before their wave function collapsed. The emitted photon is essentially a long-lasting qbit which could, with further development, be entangled with other adjacent qbits for uses in quantum computing. Another team at the University of Delft in the Netherlands, working in conjunction with UCSB, was able to detect the spin of a single electron in a diamond environment. At the same time, a group at Harvard was able to locate within a nanometer a single Carbon-11 impurity using its nuclear spin interactions.
Qbit? What's a qbit? Doh.
Categories
- Log in to post comments
More like this
Two weeks ago, now, I promised some peer=reviewed physics blogging, to compensate for the "screechy monkey" nonsense. Of course, I got distracted by other things, but I've been sitting on this paper for a while now, and I really need to get it off my desk.
The paper in question is "Quantum Register…
In the initial "Basic Concepts" post, I discussed the concept of Force in physics. This time out, I'll be talking about fields, which is a much dicier proposition. Not only are fields considerably more abstract than forces, but I've never lectured on fields in general (specific instances of fields…
While Kate was off being all lawyerly at her NAAG workshop, I spent my time visiting my old group at NIST, and some colleagues at the University of Maryland. This wasn't just a matter of feeling like I ought to do something work-like while she was workshopping-- I genuinely enjoy touring other…
I haven't posted much about life in the lab lately, because even though I'm getting to spend a bit of time in the lab, I've been so fried from this past term that I haven't had much energy for blogging. Things are finally settling into the summer routine, though, and I've gotten a little rest since…
Ask David Mermin. He'll tell you all about Qbits.
WHBIT: suggested abbreviation for "A What Bit?", likely to be a common question as bad science reporters imitate each other (silly bosons that they are).
Of course, this raises the question of the No Bozo Cloning Theorem.
I was distracted from the spelling issues by the description of a photon as a long-lasting q(u)bit. I'm dumbfounded by the article's implication that an EMITTED photon has a coherence time in the millisecond range. Is that possible? (Aside from the French superconducting microwave cavities.)
Or it it just a hairy description of some atomic (nitrogen vacancy) state which has a millisecond coherence time and whose information be coherently converted, on demand, into a photon?