Feeds

All-optical RAM to clear comms bottleneck

NTT shows off nanowatt optical memory

Secure remote control for conventional and virtual desktops

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. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
HUMAN DNA 'will be FOUND ON MOON' – rockin' boffin Brian Cox
Crowdfund plan to stimulate Blighty's space programme
Post-pub nosh neckfiller: The MIGHTY Scotch egg
Off to the boozer? This delicacy might help mitigate the effects
I'M SO SORRY, sobs Rosetta Brit boffin in 'sexist' sexy shirt storm
'He is just being himself' says proud mum of larger-than-life physicist
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
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.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Choosing a cloud hosting partner with confidence
Download Choosing a Cloud Hosting Provider with Confidence to learn more about cloud computing - the new opportunities and new security challenges.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.