Feeds

Micro-drum acts as quantum memory

NIST puts qubits in a spin

Choosing a cloud hosting partner with confidence

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
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
Mine Bitcoins with PENCIL and PAPER
Forget Sudoku, crunch SHA-256 algos
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
'This BITE MARK is a SMOKING GUN': Boffins probe ancient assault
Tooth embedded in thigh bone may tell who pulled the trigger
DOLPHINS SMELL MAGNETS – did we hear that right, boffins?
Xavier's School for Gifted Magnetotaceans
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
Canberra drone team dances a samba in Outback Challenge
CSIRO's 'missing bushwalker' found and watered
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
The next step in data security
With recent increased privacy concerns and computers becoming more powerful, the chance of hackers being able to crack smaller-sized RSA keys increases.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.