Single Atom Quantum Memory

The storage and regeneration of quantum qubits is is essential for the development of quantum computing and communications systems. Today, Holger Specht and colleagues at the Max Planck Institute for Quantum Optics in Garching, Germany, have found a way to store the qubit from a polarized photon in a single atom of rubidium and then release it again later.


(Single Atom Quantum Memory)
a, A single atom (1) (the inset shows a typical fluorescence image) is trapped at the centre of a high-finesse optical cavity using a far-detuned standing-wave dipole trap (2). b, An impinging weak coherent pulse (3) with arbitrary polarization is converted into an atomic spin excitation using a pi-polarized pump laser (4). c, This maps the photonic polarization qubit onto a long-lived superposition of the ground states of the atom. d, After a variable storage time, the polarization qubit is retrieved by the production of a single photon (5).

The trick here is first to find an atom with the suitable two-level state that will absorb photons in the right way and second, to find a way to force the photon to give up its qubit to the atom.

It turns out that rubidium has the just right energy levels. Specht and co force the atom and photon to interact by trapping them in a high quality mirrored cavity in which the photon can enter but not easily escape. It then rebounds inside until it gives up its goods to the atom.

To accept the qubit, the atom first has to be placed in the right state by a weak laser beam. A second laser beam later forces the atom to spit out the qubit in the form of an identical polarised photon.

The result is a single atom memory that can read, store and write quantum information.

The notion that a single atom could be used as a storage device is one that I first encountered while reading science fiction. In his 1951 novel Between Planets, Robert Heinlein writes about a molecule matrix:

"It is theoretically possible to have a matrix in which each individual molecule has a meaning - as they do in the memory cells of your brain. If we had such subtlety, we could wrap your Encyclopedia Britannica into the head of a pin - it would be the head of that pin..."
(Read more about Heinlein's molecule matrix)

ReadmTechnology Review for more details.

Scroll down for more stories in the same category. (Story submitted 3/15/2011)

Follow this kind of news @Technovelgy.

| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |

Would you like to contribute a story tip? It's easy:
Get the URL of the story, and the related sf author, and add it here.

Comment/Join discussion ( 1 )

Related News Stories - (" Computer ")

ARM Wants To Build Brain Chips
'Slivers of microsoft, angular fragments of colored silicon...' - William Gibson, 1984.

Robot Swarms Controlled With Augmented Reality
'You're not thinking in enough dimensions...' - Daniel Suarez, 2009.

Eterni.me - To Skype With The Dead
'Nothing... left of Jeserac but a galaxy of electrons frozen in the heart of a crystal.'- Arthur C. Clarke, 1956.

Razer Project Valerie Laptop Unfurls
'A paper thin polycarbon screen unfurled silently...' - William Gibson, 1986.

 

Google
  Web TechNovelgy.com   

Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.

 

 

 

 

 

Current News

Bat Bot Robotic Flapping-Wing Drone
'The dark birdforms dotted the mountaintops like statues of prehistoric beasts, wings outspread...'

NASA's Astronaut Rescue Ball
'Ball and closely-prisoned man plummeted downward..'

ARM Wants To Build Brain Chips
'Slivers of microsoft, angular fragments of colored silicon...'

Sky Fence - A Drone-Proof Shield Created Over Prison
'There’s still a protective field over the whole thing. It volatilizes anything that tries to get through.'

Geoengineering The Atmosphere For Climate Change
'...a uniform temperature for each degree of latitude the year round.'

Archinaut Orbiting Robotic Factory
'mass-produced only in the orbiting factories...'

Cryonic Preservation - The Last Perk You'll Ever Need
'Is there not also a law providing for voluntary suspension of animation?'

Computers Understand Humans By Watching And Modeling Them
Soon, your computer will be watching you... and judging you.

NASA Asks For Moon To Earth Delivery Ideas
'Authority's 3-g catapult was almost one hundred kilometers long...'

Musk Tunnels Wisely Restrict Drivers
Too many robots.

Robot Swarms Controlled With Augmented Reality
'You're not thinking in enough dimensions...'

MIT's C-LEARN Helps Robots Transfer Learning To Other Robots
'Talk Between Robots radio...'

Mini-Brains In A Dish
'Cultured brains on a slab.'

Rapid Automated Search For Habitable Planets Needed
'I was near enough it now to set my automatic astronomical instruments to searching it for a habitable planet.'

WatchSense Perfect For Fat-Fingered Smartwatch Owners
'Now all you had to do was wave your hand in the general direction of the components...'

Digital Construction Platform Robot 3D Prints A Building
'It extrudes material like a spider.'

More SF in the News Stories

More Beyond Technovelgy science news stories

Home | Glossary | Invention Timeline | Category | New | Contact Us | FAQ | Advertise |
Technovelgy.com - where science meets fiction™

Copyright© Technovelgy LLC; all rights reserved.