Welcome to my webpage. I am a Professor of Photonics at Optics and Photonics Centre, IIT Delhi. My research focuses on optical waveguide gratings (fiber Bragg and long-period gratings), multimode and interferometric structures, photonic time crystals, and non-Hermitian photonic concepts such as exceptional points to achieve enhanced sensitivity and robustness. A significant part of my work involves mode engineering, dispersion control, and temperature-insensitive sensor design, along with advanced signal demodulation and data-driven techniques for parameter decoupling. More broadly, my interests lie in developing high-performance photonic devices and integrated photonic systems for precision sensing and emerging applications.

We have expertise in developing sensors and solutions for detecting various biochemical reagents, e.g., E. coli bacteria, microcystin-LR molecules, and cyanobacteria, in the liquid phase. We possess IPs on many important discoveries and methods, including two US patents on optical sensors and methods. 

Prior to joining IIT Delhi, I worked as Associate Professor (2019-2022) and Assistant Professor (2014-2019) at Department of Physics, IIT Kanpur, where we developed world's first inherently temperature insensitive fiber-optic sensor for an accurate detection of E. coli bacteria in water. The sensor operates accurately over large temperature fluctuations ~40 °C, and can detect E. coli concentrations as small as 100 cfu/ml in approximately 20 minutes of time. For more details about this work please click here.

We also made discoveries related to the existence of various specific wavelengths around which the photonic sensors are most sensitive as well as the wavelengths at which the sensors show least sensitivity. More details could be obtained from my series of publications on directional coupler based sensors under publication section. 

We can provide sensor solutions and case studies related to Fiber Bragg Gratings (FBG), Long-Period Gratings (LPGs), Directional Couplers (DC), Plasmonics, and Metamaterials. 

You may contact me at smt@opc.iitd.ac.in