Photonics

Photonics is an undergraduate core course for the Engineering Physics Bachelor of Technology program at IIT Bombay. The course, which is offered under the code PH 421, covers a broad range of topics related to non-linear optical response of the medium and optical non-linearities, classical and quantum pictures, non-linear optical processes, electromagnetic wave propagation in non-linear media, coupled wave equations, second harmonic generation, optical parametric generation, optical parametric oscillators, and amplifiers, among others.

The course aims to provide a comprehensive understanding of the fundamental principles of photonics, which is the study of light and its interaction with matter. The course is taught by experienced faculty members who have expertise in this field. In addition, teaching assistants (TAs) are also involved in teaching this course and provide one hour of interaction session per week.

The course is divided into different modules that cover a wide range of topics related to photonics. The first module covers the non-linear optical response of the medium, the origin of the optical non-linearities (second and third order susceptibilities), and a synopsis of non-linear optical processes. The second module covers electromagnetic wave propagation in non-linear media, coupled wave equations for three-wave mixing, the Manley-Rowe relation, second harmonic generation, weak and strong coupling regimes, phase matching considerations, birefringence phase matching, harmonic generation with focused Gaussian beams, difference frequency generation, optical parametric generation, optical parametric oscillators, and amplifiers.

The third module covers third order non-linear optical processes, such as four-wave mixing, intensity-dependent refractive index, self-focusing, degenerate four-wave mixing and its applications, optical bistability, and optical logic. The fourth module covers stimulated Raman and Brillouin scatterings, Raman gain amplifiers, plasmonics, and their applications. The final module provides an introduction to photonic crystals and their band structure, non-linear optical processes such as second harmonic generation and optical bistability in photonic crystals, and their applications.

As a TA for this course, I assisted in teaching the course material and providing interaction sessions for the students. It was an enriching experience to see the students learn and grow their understanding of photonics. It was a privilege to be part of a course that enables students to develop the necessary skills to pursue research in photonics and contribute to the advancement of this field.