Electron-Photon Interaction: Quantum Description

This lecture provides a theoretical description of the electron-photon interaction beyond the semi-classical picture, including the quantization of the electric field. It covers the calculation of absorption and recombination rates for a two-level system using Fermi's Golden Rule. The decomposition of the recombination rate into stimulated and spontaneous emission is discussed, with a focus on the formal expression of spontaneous emission. Insights into near band edge photoluminescence transitions in bulk semiconductors are also presented.