Phase change materials may free up valuable real estate for optical data transmission

New research into the phase-changing capabilities of vanadium dioxide and infrared properties of hexagonal boron nitride holds promise for faster, more efficient optical data transmission, particularly in big data “farms” where thousands of computers must communicate to provide answers.

Joshua Caldwell

A team composed of researchers from Vanderbilt University, the University of Georgia and Kansas State University learned that the broad gradient in the infrared optical properties of vanadium dioxide, as it transitions from insulating to metallic, offers distinct implications for nanophotonics. That makes it possible to have on-chip manipulation of light at the nanoscale length-scales.

“By using this phase-change material, you change the local environment and, thus, wave propagation,” said Joshua Caldwell, associate professor of mechanical engineering and electrical engineering. “To achieve on-chip control of light propagation, this is required, not simply modulating the light on and off.”

Caldwell and his collaborators published a paper about their work, titled “Reconfigurable infrared hyperbolic metasurfaces using phase change materials,” Oct. 22 in the journal Nature Communications.

Richard Haglund

Co-author Richard Haglund, Stevenson Professor of Physics, explained the discovery’s potential in data transmission.

“On a chip, 80 percent of the real estate is taken up by wiring,” he said. “Wires have resistance, their transmission speed is limited and they get hot. Likewise, data lines that transmit signals using electrons have the same problem. If you could use photons to move information from Point A to Point B, you’d be making extremely high-speed data transfers without generating heat.”

The work was funded by National Science Foundation grant numbers CMMI 1538127 and 1553251 and Air Force Office of Scientific Research grant number FA9559-16-1-0172.