Mar 20 2015
A team of researchers from Tel Aviv University (TAU) have developed a new nanoscale 'metamaterial' with the aim of creating the ultra-high-speed optical computing systems of the future.
Today more than ever before, the world is connected digitally via computers, smartphones and tablets. Considering the enormous quantities of data being exchanged daily, adequate technology support has become very important. As a result, engineers and scientists are very keen to produce faster computing systems with the ability to support considerable amounts of data processing and data transfer.
TAU researchers published their study in Nature Photonics. The team was headed by Dr. Tal Ellenbogen and consisted of Nadav Segal, Shay Keren-Zur, and Netta Hendler from the Department of Physical Electronics at TAU's School of Electrical Engineering and TAU's Center for Nanoscience and Nanotechnology.
The researchers explained that these 'nonlinear metamaterials' possessed physical properties not present in nature, and that form the basis for global companies like Intel and IBM to shift from electronic to optical computing.
Dr. Ellenbogen analyses the relationship between matter and light at the nanoscale level in his TAU lab so as to discover the fundamental physical mechanisms, which then can be utilized to create new optical and electro-optical parts.
"Optical metamaterials have been studied for their intriguing and unusual properties for the last 15 years," said Dr. Ellenbogen. "Our work shows that, with the proper design, they can also be used to develop new types of active optical components essential to the manufacture of ultra-high-speed optics-based computer chips."
A material’s chemical composition determines the interaction between a material and light in the case of natural materials. However in the newly discovered optical materials, control of the interaction is possible through the formation of fine nanostructures and novel optical phenomena can be detected.
For instance, when the interaction strength and the light field’s strength are not directly proportional to each other, the effects of nonlinear optics are observed. Using these effects, active optical systems can be created.
In some cases, these artificial optical materials are termed as optical metamaterials, and their nanoscale building blocks are termed as "optical meta-atoms."
"Future on-chip communications systems are expected to change from relying solely on electronics to relying on photonics — that is, the qualities and mechanics of light — or hybrid electronic-photonic systems," said Dr. Ellenbogen. "These photonic on-chip communications systems will consist of active nonlinear nanoscale optical elements. Our research opens the door to consider nonlinear metamaterials as the active nanoscale components in future on-chip communications.
"By merging two disciplines in optics — metamaterials and nonlinear photonic crystals — we are opening the door to constructing novel active nonlinear devices based on metamaterials and to new fundamental studies altogether," said Dr. Ellenbogen.
Currently, the TAU researchers are investigating ways to create the nonlinear interaction in an efficient manner by utilizing multilayered metamaterial structures and by exploring various metamaterial building blocks.
All of the research was conducted at the Laboratory for Nanoscale Electro-Optics at TAU's Center for Nanoscience and Nanotechnology, and was supported by the Israel Science Foundation, the European Commission Marie Curie Career Integration Grant, and the Tel Aviv University Center for Renewable Energy. For this research Nadav Segal won the The Feder Family Award for Best Student Work in Communications.