Feeds

Micro-drum acts as quantum memory

NIST puts qubits in a spin

Build a business case: developing custom apps

Memory is one of the difficult bits of quantum computing. For example, while the polarisation of a photon encodes a quantum state, it's very difficult to get photons to stay where they're put.

A group of researchers from JILA – a joint institute between the University of Colorado and the National Institute of Standards and Technology – has demonstrated a different approach to capturing quantum states in memory: they're using a microscopic spinning platter to do the job.

At the moment, it's not very accurate: the spinning drum captured the vertical and horizontal positions of a microwave signal at a point in time (the quantum state they were trying to capture), but that state could only be retrieved with 65 percent accuracy.

The micro-drum was created by NIST in 2011. Because it's embedded in a resonant circuit, the drum is able to beat at different frequencies. That means the electrical energy in the microwaves can be captured as mechanical energy as a phonon (a unit of vibration).

NIST micro-drum

NIST's micro-drum and circuit (colorised image)

To get this interaction happening at the quantum level, the researchers had to cool the drum to its lowest-possible energy state, at which point it has less than one quantum of its own energy. The microwaves used to cool the drum to its ground state also transfer information about the their quantum states to the drum, in the form of a temporary state beating at the received frequency.

The researchers also found a way to turn the microwave-drum interaction on and off, based on the intensity of the microwave tone.

If the researchers can improve the performance of the quantum memory, they'll end up with something that's compatible – both in size and in the fabrication techniques used – with devices that NIST uses as qubits.

NIST says in practice, the micro-drum is somewhat like the delay-line memory used in early computers like NIST's SEAC of the 1950s, in which computation values were temporarily stored as acoustic waves travelling down a column of a fluid like mercury.

The NIST research is to published in Nature and its announcement is here. ®

Bootnote: The researchers note that the drum is actually a quasi-quantum memory: its beat is a classical system, but in a quantum-noisy environment. This author isn't physicist enough to completely understand the distinction. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Boffins attempt to prove the UNIVERSE IS JUST A HOLOGRAM
Is this the real life? Is this just fantasy?
Our LOHAN spaceplane ballocket Kickstarter climbs through £8000
Through 25 per cent but more is needed: Get your UNIQUE rewards!
China building SUPERSONIC SUBMARINE that travels in a BUBBLE
Shanghai to San Fran in two hours would be a trick, though
LOHAN tunes into ultra long range radio
And verily, Vultures shall speak status unto distant receivers
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
Galileo, Galileo! Galileo, Galileo! Galileo fit to go. Magnifico
I'm just a poor boy, nobody loves me. But at least I can find my way with ESA GPS by 2017
EOS, Lockheed to track space junk from Oz
WA facility gets laser-eyes out of the fog
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Backing up distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.