👉 Laser physics, particularly in the context of laser math, revolves around the principles of stimulated emission and coherent light generation. When an atom or molecule in an excited state encounters a photon with the exact energy difference between its excited state and a lower energy state, it can stimulate the emission of an identical photon, both in phase and direction. This process, known as stimulated emission, is the foundation of laser operation. The laser medium, often a gas, solid, or fiber, is pumped to a higher energy state using external energy sources like electrical discharge or optical pumping. The emitted photons then travel through a resonant cavity, which consists of mirrors that reflect the light back and forth, amplifying it through repeated stimulated emissions. The cavity's length and mirror reflectivity determine the laser's output characteristics, such as wavelength, beam quality, and coherence. The math behind lasers involves solving equations for photon statistics, population inversion, and gain saturation to optimize the laser's performance. This intricate interplay of quantum mechanics and classical optics results in the highly coherent, monochromatic, and directional light that defines lasers.
