Laser technology, celebrating its 50th anniversary, has revolutionized science and technology. A laser is a device that amplifies light through stimulated emission of photons. The key components are a gain medium (atoms, molecules, or semiconductor), an optical cavity with mirrors, and a pumping mechanism to excite the medium.
When the gain medium is excited, photons are emitted. In a laser, these photons stimulate other excited atoms to emit more photons in phase, creating a coherent, collimated light beam. This coherence allows lasers to be focused to tiny spots or transmitted over long distances with minimal spreading.
Lasers have countless applications, from data storage and optical communication to medical procedures and scientific research. They enable cooling of atoms to near absolute zero temperatures and are crucial for quantum computing and encryption.
The article highlights how lasers, despite being “a solution in search of a problem” when first introduced, have become indispensable tools across nearly every field of modern life. Their ability to manipulate light in novel ways continues to unlock new scientific discoveries and technological innovations.
Source: https://www.nist.gov/director/pao/nists-role-laser-measurements-and-applications/what-laser
Keywords: lasers, quantum, photons, coherence, cooling
