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 ")

Atomristors - Atomic Memristors - Using Thin Nanomaterials
'I could almost feel those little tunnel junction neuristors working, forming their own interconnections as I operated it.' - Robert Heinlein, 1966.

RNA-Based Biocomputing Device
Living things can sense and analyze complex signals in living cells.

Loihi Chip Mimics Human Brain's Neurons And Synapses
'You can hook a Thorsen tube into a control circuit... and the tube will "remember" what was done and can direct the operation...' - Robert Heinlein, 1956.

Brain Connected To Internet - ‘Brainternet'
Fascinating! or thoughts to that effect.

 

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

A 'Genuine Nanorobotic Production Factory'
'Microscopic machinery, smaller than ants, smaller than pins, working energetically, purposefully - constructing something...'

Neuromorphic Computer Offers Non-von Neumann Architecture
Fires faster than brain at 1/10K energy.

Evorus Your Crowd-Powered Conversational Assistant
'...the DS [Daily Schedule] was suddenly transformed into a valued confidante.'

Mealworms Food Of The Future
Get your grubs on.

Alibaba's AI May Read Better Than You
'Mike ... could accept other languages and was doing technical translating - and reading endlessly.'

Musk's Boring Flamethrower
'Skeletons in tatters. Burned by a flesh gun'

Humanity Star LEO Advertisement?
'Everyone has noticed those enormous advertisements...'

Nissan ProPILOT Slippers Are Self-Parking, Autonomous
Beyond science and fiction.

Atomristors - Atomic Memristors - Using Thin Nanomaterials
'I could almost feel those little tunnel junction neuristors working, forming their own interconnections as I operated it.'

Bigelow Prepares Inflatable Lunar Hotel
'Suddenly, hitherto unheard-of sums of money became available for investment in civilian orbital stations.'

Drunk Driver Of Tesla Claims Autopilot Was In Charge
'Mr. Garden, you are in no condition to drive.'

Medical Exoskeleton From Cyberdyne Gets FDA Approval
It's been a long road for HAL-5; I started writing about it in 2005.

Fungi-Infused Concrete Repairs Itself
'I noticed that curious mottled knots were forming, indicating where the room had been strained and healed faultily.'

Shiftwear Display Shoes
'He unlaced her shoe and glanced at its readout.'

NASA SEXTANT First With X-Ray Nav In Space
'You need at least four beacons for an accurate fix.'

GM Introduces Cruise AV With No Steering Wheel
'How about the steering wheel?' ... 'I do not need one.'

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.