Communicating at the speed of light with graphene

(Nanowerk News) Imagine how much we could accomplish in a day if we could exchange messages at the speed of light.
Thin two-dimensional materials, made atomic layer by atomic layer, may enable communications at higher speed and lower power consumptions than previously realized. Multidisciplinary research in this field is happening now at the University of Delaware.
Tingyi Gu, assistant professor of electrical and computer engineering at the University of Delaware
Tingyi Gu, assistant professor of electrical and computer engineering at the University of Delaware.
For this work, Tingyi Gu, an assistant professor in the Department of Electrical and Computer Engineering, is one of 43 scientists nationwide to receive a grant this year through the Air Force Office of Scientific Research (AFOSR) Young Investigator Program this year.

The AFOSR Young Investigator Program was established to foster creative basic research. It is awarded to scholars with exceptional ability and promise who have earned their doctoral degrees within the last five years.

Under this three-year, $450,000 grant, Gu is developing "next-generation hybrid optical communications"--small, lightweight devices for efficient light generation and transportation, enabling high speed and low power optical interconnects, which is an interface between electronic signals in computers and optical fiber communication signals.
In optical communications, signals are transmitted via light. Fiber communication is the backbone bundling all the signals.
In contrast, the communications devices you use everyday, like laptops and phones, use wireless radio signals to transmit signals.
To build devices for optical communications, Gu first uses software to design the devices, optimizing their optical, electronic and thermal properties. Then, she will work with the team at the UD Nanofabrication Facility to make the devices.
"The UD Nanofabrication Facility team is actively working with Prof. Gu's group on this project and we have recently made promising progress on fabricating those high quality nanophotonic devices on a large scale," said Iulian Codreanu, Ph.D., director of operations at UD NanoFab.
The devices start with silicon, a material commonly used in photonics--the study of light and its applications. Then graphene, a two-dimensional material made from a single layer of atoms, is bonded onto silicon chips. Graphene can improve chip performance, including generation, amplification, modulation, and detection of optical signals.
"Its unique structure gives it unique electronic properties not enabled by bulk materials," said Gu.
In 2010, the pioneers of graphene research, located at the University of Manchester, won the Nobel Prize in Physics. Since then, "two-dimensional materials have been a hot area of research," said Gu.
Gu isn't just making devices--she is testing them in order to improve speed, performance, and scalability of devices made with these materials. These could be the basis of next-generation optical interconnect systems in Air Force infrastructures, she said.
"Together we are doing very sharp engineering in combination with hot science," said Gu. "This grant gives me more opportunity to tap the potential of my research."
Gu's students will also benefit from this award.
"This is a wonderful opportunity for students to get trained to understand the process from beginning to end," she said, "which is critical for their future careers."
Gu's work with photonic devices has also garnered attention from NASA, which granted her an Early Career Faculty Award earlier this year.
Dennis Prather, Engineering Alumni Professor in the Department of Electrical and Computer Engineering and Dr. Gu's faculty mentor, has been studying silicon photonics for nearly two decades. He is impressed by Gu's success thus far.
"I'm certain she will be a future pillar of our department and I'm already so proud to call her my colleague," he said.
Source: By Julie Stewart, University of Delaware