Capture light to store it as memory

The aim is to allow large quantities of data to be stored directly on an integrated optical chip, rather than being processed and stored electronically, as happens today.

According to Exeter University:

The scientists used so-called phase change materials at the heart of their all-optical memory. The distinguishing feature of these materials is that they radically change their optical properties depending their phase state, i.e. depending on the arrangement of the atoms in the material. This changeability – between crystalline (regular) and amorphous (irregular) states – allowed the team to store many bits in a single integrated nanoscale optical phase-change cell.

Professor David Wright, of the University of Exeter’s Engineering department, commented:

“With our prototype we have, for the first time, a nanoscale integrated optical memory that could open up the route towards ultra-fast data processing and storage. Our technology might also eventually be used to reproduce in computers the neural-type processing that is carried out by the human brain.”

“The all-optical memory devices we have developed provide opportunities that go far beyond any of the approaches to optical data processing available today,” said Professor Wolfram Pernice, from the Institute of Physics at Münster University and who led the work.

“Optical bits can be written in our system at frequencies of up to a gigahertz or more,” adds Professor Harish Bhaskaran from Oxford University in England, one of the lead co-authors, “and our approach can define a new speed limit for future processors, by delivering extremely fast on-chip optical data storage” In addition, he says, “the written state is preserved when the power is removed, unlike most current on-chip memories”.