Feeds

All-optical RAM to clear comms bottleneck

NTT shows off nanowatt optical memory

New hybrid storage solutions

Japanese researchers are claiming a breakthrough in all-optical memory, one of the key bottlenecks remaining in the optical communications world.

The high throughput of optical communications systems brings its own problem: any function that can’t be performed in the optical domain demands an opto-electric conversion, creating a bottleneck in the system. This has put a premium on research into optical switching, amplification and signal regeneration.

Memory is a tough nut to crack, however: it demands that a photon’s state be captured, retained and read out – all without converting the signal back to electrons, and in a repeatable and cheap fashion.

The NTT researchers say they have created an ultra-low-power optical RAM using optical cavities that represent a 1 or 0 by either passing or blocking light. The memory cell uses a material based on an indium gallium arsenide strip buried in gallium arsenide.

It acts as a memory because the indium-gallium arsenide strip changes its refractive index when exposed to a laser. The light beam it’s trying to “remember” will be blocked or passed depending on the state of the strip. A second pulse of laser on the “control” strip reverses its state.

While it only retains state for about a microsecond, the researchers say that’s long enough for other system components to use the stored information (and four times the previous record for an all-optical memory). Importantly, they also say the optical cavity approach consumes very low power – according to the Nature Photonics abstract, 30 nW, which is “more than 300 times lower than the previous record”. ®

Bootnote: Proposals for optical memory have existed for a surprisingly long time. For example, this Wikipedia entry describes an approach using a loop of photo-emissive and photo-sensitive materials from the 1950s, as an attempt to solve the problems of memory speed in early computers. ®

Providing a secure and efficient Helpdesk

More from The Register

next story
Boffins: Behold the SILICON CHEAPNESS of our tiny, radio-signal-munching IoT sensor
Single ant-sized Stanford chip combines radio, 'puter, antenna
Thought that last dinosaur was BIG? This one's bloody ENORMOUS
Weighed several adult elephants, contend boffins
Drones swarm over bearded Brit billionaire's island getaway
Just to take lovely pictures though, after Richard Branson invests in 3D Robotics
Chelyabinsk-sized SURPRISE asteroid to skim Earth, satnav birds
Space rock appears out of nowhere, buzzes planet on Sunday
California blue whale numbers soar to historical levels, say boffins
Still far too many of them being struck by US ships, mind
City hidden beneath England's Stonehenge had HUMAN ABATTOIR. And a pub
Boozed-up ancients drank beer before tearing corpses apart
'Duck face' selfie in SPAAAACE: Rosetta's snap with bird comet
Probe prepares to make first landing on fast-moving rock
prev story

Whitepapers

Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.