This repository contains the term project completed for the PH3203: Advanced Quantum Mechanics course (6th semester) at IISER Kolkata.

The project presents a theoretical study of the Delayed Choice Quantum Eraser experiment. It includes:

• A detailed review of the physical concepts involved, such as complementarity, entanglement, and delayed choice.
• A step-by-step derivation of the two-photon entangled state produced via spontaneous parametric down-conversion (SPDC).
• Analytical calculations of coincidence detection rates for different detector configurations.
• Explanation of how interference patterns emerge or disappear depending on the availability of which-path information.
• Discussion of the experimental observations reported in the original quantum eraser experiments.

The repository primarily serves as a record of the theoretical analysis and derivations carried out as part of the course term project.