A Photonic Integrated Circuit (PIC) is analogous to an electronic integrated circuit, where photons are manipulated at sub-micron scale. Ability to confine and control flow of light in a sub-micron feature such as an integrated optical waveguide allows us to study and exploit the properties of light. The research group of Prof. Shankar K. Selvaraja is involved in developing integrated photonic devices and circuits to manipulate the flow of light in sub-micron scale features. Some of the fundamental devices developed are wavelength selective filters, light-chip couplers, optical modulators, photodetectors and light source, all these components are either monolithically or heterogeneously integrated on a single chip. The primary goal of the PIC research program run by Prof. Shankar K. Selvaraja is to create a generic high-volume manufacturable PIC platform that can operate in multiple wavelength ranges for a broad range of applications.
Photonic Integrated Sensing Circuits (PhISCs): As part of the biosensors thrust area in Prof. Manoj Varma‘s lab, PIC technology is being applied to the sensing of bio-molecules. Research explorations in this area includes the development of suspended waveguide structures for opto-mechanical sensing and the development of a multiplexed Silicon Micro-ring resonator platform.
For nonlinear applications, integrated devices are especially interesting. The nonlinear coefficient of CMOS compatible materials like silicon, silicon nitride etc are ‘2’ orders of magnitude higher than that of optical fibres, while the confinement of light in nanophotonic waveguides can be ‘3’ orders of magnitude higher. This results in a net figure of merit ‘5’ orders of magnitude higher than the common nonlinear processing element, namely silica optical fibres. Device length scales can be shrunk from kilometre scales to mere centimetres. On-chip nonlinear optics has become an exciting technology for various applications such as optical communications, metrology, biophotonics, microwave photonics and for mid-IR light sources. This line of research is actively pursued in the groups of Prof Supradeepa V R and Prof Shankar Selvaraja.
 Associate Professor |