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Stimulated emission is a process in which an incoming photon of the same energy as an excited atom or molecule causes that atom or molecule to release a second photon with the same energy, direction, and phase. This results in the amplification of light and is the principle behind lasers.
A Ne-He laser is a type of gas laser that uses a mixture of neon and helium gases as the lasing medium. It operates in the visible and infrared spectrum and is commonly used in medical and scientific applications.
In a Ne-He laser, electrons in the neon atoms are excited by an electrical discharge, causing them to move to higher energy levels. When these electrons return to their ground state, they emit photons. These photons then stimulate other excited neon atoms to emit photons of the same energy, resulting in a chain reaction of stimulated emission and the production of a coherent beam of light.
Ne-He lasers have a number of advantages, including a longer lifetime compared to other gas lasers, a wider range of wavelengths, and a higher power output. They also have a relatively low cost and are commonly used in scientific research, medical treatments, and industrial applications.
Spontaneous emission is the natural process in which an excited atom or molecule releases a photon without any external stimulus. In contrast, stimulated emission occurs when an incoming photon stimulates the release of a second photon with the same energy, direction, and phase. This results in a more precise and coherent beam of light, making stimulated emission the principle behind laser technology.
