Quick Links
Sumit Kotwal
Department: Photonics Science and Engineering Programme
Guide: Debabrata Goswami
Research Topic
Photothermal Phenomena & Spectroscopy: Studying non-radiative relaxation pathways, molecular interactions, and photothermal transport properties through Z-scan and time-resolved thermal lens spectroscopy.
Ultrafast & Non-linear Optics: Utilising high-precision femtosecond laser setups such as pump-probe techniques including dual beam thermal lens spectroscopy to analyse photothermal effects in liquid systems.
Semiconductor Device Engineering (Master's Thesis work): Developing low-resistance ohmic contacts on wide-bandgap materials like Gallium Nitride (GaN) by fabricating, characterising, and optimising multi-layer thin-film metallization schemes using electron-beam evaporation and photolithography.
Thermal Process Optimisation (Master's Thesis work): Examining the impact of rapid thermal annealing parameters on device performance with Circular Transmission Line Measurements (CTLM) to reduce contact resistance in high-power laser diode applications.
Education
Integrated Masters of Science (Physics),
Central University of Rajasthan, Ajmer, India
Selected Publications
Journal Publications
A. Sharma, S. Kant, S. Kotwal, D. Goswami, Revealing synergistic photo-thermal lens effects in binary DMF mixtures
J. Mol. Liq. 438 (2025) 128734
Conference Proceedings
S. Kotwal, A. Sharma, D. Goswami, Photothermal Transport Perturbation in Methanol-Water Binary System Using Non-Absorbing Fluorescein Dye
Frontiers in Optics + Laser Science 2025 Optica Publishing Group, (FiO, LS), Washington, D.C., 2025, p. JV8A.4.
Bio
Sumit Kotwal is a PhD researcher specializing in semiconductor device fabrication and ultrafast optical spectroscopy. He earned his Integrated Master of Science in Physics from Central University of Rajasthan, India, under Prof. Rajendra Charandeo Pawar's guidance. During his master’s studies, he collaborated with the Solid State Physics Laboratory (SSPL) in New Delhi on his dissertation, supervised by Mr. Abhishek Sharma (Scientist F), focusing on cleanroom fabrication and process optimization of low-resistance ohmic contacts for high-power laser diodes.
After completing his master's, Sumit joined the Indian Institute of Technology (IIT) Kanpur for his doctoral research. He is currently pursuing a PhD through the joint program between IIT Kanpur and La Trobe University, co-supervised by Prof. Debabrata Goswami at IIT Kanpur and Prof. Adam Mechler at La Trobe University. His current research at IIT Kanpur involves advanced optical characterization, examining non-radiative molecular dynamics and photothermal effects using Z-scan and time-resolved thermal lens spectroscopy with pump-probe techniques. His expertise bridges cleanroom microfabrication, including photolithography and thin-film deposition, and high-precision ultrafast laser spectroscopy.