Home > Active laser medium
Within a laser, the active laser medium is the material that exhibits optical gain. This gain is generally generated by stimulated emission on electronic or molecular transitions to a lower energy state, starting from a higher energy state to which it had been previously stimulated by means of a pump source.Examples of active laser media include:
- certain crystals, typically doped with some rare-earth ions (e.g. of neodymium, ytterbium, or erbium) or transition metal ions (e.g. of titanium or chromium)
- glasses, e.g. silicate or phosphate glasses, also doped with some laser-active ions
- gases, e.g. mixtures of helium and neon], or neon], or argonArgon was also a codename used for the KH-5 reconnaissance satellite. Argon is the chemical element in the periodic table that has the symbol Ar and atomic number 18. The third noble gas, in period 8, argon makes up about 1% of the Earth's atmosphere. or carbon dioxideCarbon dioxide is an atmospheric gas composed of one carbon and two oxygen atoms. One of the best known of chemical compounds, it is frequently called by its formula: :CO (pronunciation: "see oh two") Carbon dioxide results from the combustion of organic
- semiconductorA semiconductor is a material that is an insulator at very low temperature, but which has a sizable electrical conductivity at room temperature. The distinction between a semiconductor and an insulator is not very well-defined, but roughly, a semiconductos, e.g. gallium arsenideGallium arsenide (GaAs) is a chemical compound composed of gallium and arsenic. It is an important semiconductor, and is used to make devices such as microwave frequency integrated circuits, infrared light-emitting diodes and laser diodes. Properties Gene (GaAs), indium gallium arsenide (InGaAs), or gallium nitride (GaN)
- liquid solutions of certain dyeA dye can generally be described as a coloured substance that has an affinity to the substrate to which it is being applied. The dye is usually used as an aqueous solution and may require a mordant to improve the fastness of the dye on the fibre. In contrs
Pumping of gain media (i.e., the supply of energy) can be achieved with electrical currents (e.g. in semiconductors, or in gases via high-voltage discharges) or with light, which may be generated with discharge lamps or with other lasers. More exotic gain media can be pumped by chemical reactions, nuclear fissionIn physics, fission is a nuclear process, meaning it occurs in the nucleus of an atom. Fission is when the nucleus splits into two or more smaller nuclei plus some by-products. These by-products include free neutrons and photons (usually gamma rays)., or with high-energy electron beams.
1 See also
- Laser constructionA laser system generally consists of three important parts: An energy source (usually referred to as the pump or pump source ; A gain medium or laser medium A mirror, or system of mirrors, forming an optical resonator. The pump source is the part that pro, Laser scienceLaser science is a branch of optics that describes the theory and practice of lasers. Laser science is principally concerned with quantum electronics, the design of optical resonators, the physics of laser media, the temporal evolution of the light field, List of lasers
2 External link
Quantum mechanics
Lasers
