Fiber lasers and fiber amplifiers

Nowadays, lasers have become ubiquitous in our daily lives. But why are lasers such indispensable light sources across a multitude of applications? It boils down to their remarkable ability to concentrate high-intensity light within an exceptionally narrow spectral band, ensuring coherence over distances of hundreds of kilometers.

Laser technology has advanced to encompass nearly the entire electromagnetic spectrum, spanning from ultraviolet to mid-infrared wavelengths. This broad spectrum of wavelengths proves beneficial across various sectors of our lives, including healthcare, telecommunications, industry, entertainment, and more.

Fundamentals of fiber laser set-up

To build a laser, primary it is required a gain medium, which could be a solid, liquid, gas, or semiconductor, serving to amplify light through stimulated emission. This medium necessitates an energy source, whether electrical current, flash lamps, or another laser for excitation to higher energy states. An optical cavity or resonator, comprising highly reflective mirrors, encloses the gain medium, enabling photons to stimulate further emissions as they bounce back and forth. One mirror within the cavity functions as a partially reflective output coupler, permitting a portion of the light to exit as the laser beam.

Supporting infrastructure includes a power supply, control electronics, and potentially a cooling system to regulate temperature and prevent overheating. Additional optical components such as lenses and beam splitters facilitate beam manipulation as per specific r