Researchers at Columbia University said they have developed a hybrid graphene-silicon/photonic chip that enables ultra low-power optical information processing.
According to the research result scheduled to be published in the August issue of Nature Photonics, the scientists were able to build the chip in a way that its system parameters such as transmittance and wavelength conversion can change with the input power level.
Additionally, they were able to create a radio frequency carrier on top of the transmitted laser beam and control its modulation with the laser intensity and color. As its ability to tune the radio frequency was explored, the researchers discovered that the hybrid chip enabled them to achieve "radio frequency generation with a resonant quality factor more than 50 times lower than what other scientists have achieved in silicon."
In a statement, professor of mechanical engineering Chee Wei-Wong said that the team of scientist was able to generate "new optical frequencies through nonlinear mixing of two electromagnetic fields at low operating energies, allowing reduced energy per information bit." He added: "This allows the hybrid silicon structure to serve as a platform for all-optical data processing with a compact footprint in dense photonic circuits."
As most other graphene research projects, this work is in its nascent stages and a commercial production is not in sight yet. However, the potential opportunity opened by graphene and new research results surfacing on an almost daily basis is stunning.
"We have been able to demonstrate and explain the strong nonlinear response from graphene, which is the key component in this new hybrid device," said Tingyi Gu, the study's lead author and a Ph.D. candidate in electrical engineering. "Showing the power-efficiency of this graphene-silicon hybrid photonic chip is an important step forward in building all-optical processing elements that are essential to faster, more efficient, modern telecommunications. And it was really exciting to explore the magic of graphene's amazingly conductive properties and see how graphene can boost optical nonlinearity, a property required for the digital on/off two-state switching and memory."