Amplification by Stimulated Emission of Radiation (ASE)

Amplification by Stimulated Emission of Radiation (ASE) refers to a process where excited atoms or molecules emit light coherently when influenced by an incoming photon. When these excited particles encounter a photon matching their emission energy, they release additional photons that are in phase and aligned in direction, amplifying the original light. This process is fundamental to the operation of lasers, where a small initial light is amplified to produce a powerful, focused beam. ASE can occur naturally in laser materials and is crucial for understanding how lasers generate intense, coherent light through controlled atomic or molecular interactions.