Tag Archives: Quentin Glorieux

With a song in your heart and multiplexed images in an atomic vapor

A specific piece of research has inspired a song with lyrics based on the text of a research paper and, weirdly, it works. You will have a song in your heart and on your lips and it’s all to do with storing images in an atomic vapor,

Hot, hot, hot, eh?

As for the research paper itself (Temporally multiplexed storage of images in a Gradient Echo Memory), it’s currently availab.e at arXiv.org or in Optics Express, Vol. 20, Issue 11, pp. 12350-12358 (2012) DOI: 10.1364/OE.20.012350(authors: Quentin Glorieux, Jeremy B. Clark, Alberto M. Marino, Zhifan Zhou, Paul D. Lett). The May 29, 2012 news item on Nanowerk offers some tantalizing tidbits about the work,

The storage of light-encoded messages on film and compact disks and as holograms is ubiquitous—grocery scanners, Netflix disks, credit-card images are just a few examples. And now light signals can be stored as patterns in a room-temperature vapor of atoms. Scientists at the Joint Quantum Institute [JQI] have stored not one but two letters of the alphabet in a tiny cell filled with rubidium (Rb) atoms which are tailored to absorb and later re-emit messages on demand. This is the first time two images have simultaneously been reliably stored in a non-solid medium and then played back.

In effect, this is the first stored and replayed atomic movie. Because the JQI researchers are able to store and replay two separate images, or “frames,” a few micro-seconds apart, the whole sequence can qualify as a feat of cinematography.

Here’s a little more detail about how this was done and some information about the implications,

Having stored one image (the letter N), the JQI physicists then stored a second image, the letter T, before reading both letters back in quick succession. The two “frames” of this movie, about a microsecond apart, were played back successfully every time, although typically only about 8 percent of the original light was redeemed, a percentage that will improve with practice. According to Paul Lett, one of the great challenges in storing images this way is to keep the atoms embodying the image from diffusing away. The longer the storage time (measured so far to be about 20 microseconds) the more diffusion occurs. The result is a fuzzy image.

Paul Lett plans to link up these new developments in storing images with his previous work on squeezed light. “Squeezing” light is one way to partially circumvent the Heisenberg uncertainty principle governing the ultimate measurement limitations. By allowing a poorer knowledge of a stream of light—say the timing of the light, its phase—one gain a sharper knowledge of a separate variable—in this case the light’s amplitude. This increased capability, at le ast for the one variable, allows higher precision in certain quantum measurements.

“The big thing here,” said Lett, “is that this allows us to do images and do pulses (instead of individual photons) and it can be matched (hopefully) to our squeezed light source, so that we can soon try to store “quantum images” and make essentially a random access memory for continuous variable quantum information. The thing that really attracted us to this method—aside from its being pretty well-matched to our source of squeezed light—is that the ANU [Australian National University] group was able to get 87% recovery efficiency from it – which is, I think, the best anyone has seen in any optical system, so it holds great promise for a quantum memory.”

I may never totally understand this work but at least I now have a song to sing and for anyone who wants more details, the May 27, 2012 news item on Nanowerk provides details and images, as well as, another opportunity to watch the song.  I did check out the video on YouTube and found that it’s by therockcookiebottom and is part of a project, Song A Day: 1000 Days and Counting that singer-songwriter, Jonathan Mann started in Jan. 2009. I imagine that means he  must be nearing the end. Thank you Jonathan for a very entertaining and educational song. He does offer memberships to support him and his song-a-day project and opportunities to hire him for any songwriting projects you may have.