Integrated all-photonic chip uses DVD phase-change material as nonvolatile memory

Sept. 22, 2015
Device has multilevel memory capability.

(Image: Oxford University)

The first integrated on-chip nonvolatile all-photonic memory has been created by scientists at Oxford University (Oxford, England), the University of Münster (Münster, Germany), Karlsruhe Institute of Technology (KIT; Eggenstein-Leopoldshafen, Germany), and the University of Exeter (Exeter, England).1 The new device uses the phase-change material Ge2Sb2Te5 (germanium-antimony-tellurium, or GST), which is the same material used in rewritable CDs and DVDs and switches from an amorphous to a crystalline state and back when prompted by light.

The wavelength-multiplexed device has single-shot reading and switching energies at a 1 GHz speed are as low as 13.4 pJ. The device is a multilevel memory, meaning that various state rations, from entirely crystalline to completely amorphous and in between, can be written, thus storing more than one bit per site.

Researchers have tried to create on-chip photonic memory before, but the results have always been volatile, requiring power in order to store data.

"This is the first ever truly nonvolatile integrated optical memory device to be created," says Carlos Ríos, one of two lead authors of the paper. "And we've achieved it using established materials that are known for their long-term data retention; GST remains in the state that it's placed in for decades."



1. Carlos Rios et al., Nature Photonics (2015); doi: 10.1038/nphoton.2015.182

Sponsored Recommendations

Next generation tunable infrared lasers

Nov. 28, 2023
Discussion of more powerful and stable quantum cascade tunable infrared lasers, applications, and test results.

What AI demands mean for data centers

Nov. 28, 2023
The 2023 Photonics-Enabled Cloud Computing Summit assembled by Optica took an aggressive approach to calling out the limitations of today’s current technologies.

SLP feature for lighting control available on cameras offering

Nov. 28, 2023
A proprietary structured light projector (SLP) feature is now available on the company’s camera series, including the ace 2, boost R, ace U, and ace L.

Chroma Customer Spotlight - Dr. David Warshaw, About his Lab

Nov. 27, 2023
David Warshaw, Professor and Chair of Molecular Physiology and Biophysics at the University of Vermont (UVM), walks us through his lab. Learn about his lab’s work with the protein...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!