Researchers at Massachusetts Institute of Technology have proposed a new kind of data-storage system that could eventually lead to computer and data-storage chips capable of packing a far greater punch than today's options much faster and for much less energy.
The system combines ferroelectric materials - the kind often used for data storage - with graphene, a two-dimensional form of carbon and seeming wonder product known for its exceptional electronic and mechanical properties, as well as being the strongest material in the world.
The new system works by controlling waves called surface plasmons. These waves are oscillations of electrons confined at interfaces between materials and, in the new system operate terahertz frequencies. Believed to be ideal for next-generation computing devices, such frequencies are the same as those that lie between far-infrared light and microwave transmissions.
The system would provide a new way to create interconnected devices using light waves, such as fiber-optic cables and photonic chips, with electronic wires and devices.
At this point, similar interconnection points often cause a bottleneck, slowing the transfer of data and adding to the number of components needed.
Furthermore, the new system allows waves to be concentrated at much smaller length scales, which could one day provide for a tenfold gain in the density of components placed in a chip, according to the scientists.
The initial proof-of-concept device achieves all this through a small piece of graphene sandwiched between two layers of the ferroelectric material in order to make simple, switchable plasmonic waveguides.
Light can then be confined in these waveguides down to one part in a few hundreds of the free-space wavelength, representing an order-of-magnitude improvement over any comparable waveguide system.
"This opens up exciting areas for transmitting and processing optical signals," associated professor of mechanical engineering Nicholas Fang explained in a press release.
Additionally, the work may allow for a new way to read and write electronic data into ferroelectric memory devices at extremely high speeds, Fang and his colleagues said.
Dimitri Basov is a professor of physics at the University of California, San Diego and, while not connected to the research, had much to say on it, saying the MIT team "proposed a very interesting plasmonic structure, suitable for operation in the technologically significant [terahertz] range."
Furthermore, he said his research groups will, going forward, try to implement the devices.
However, Basov does issue a warning, which is that the "key issue, as in all of plasmonics, is losses. Losses," he said, "need to be thoroughly explored and understood."
The study was published in the journal Applied Physics Letters and was funded by the National Science Foundation and the Air Force Office of Scientific Research.