photonic

Photonic is an adjective used to describe phenomena, materials, devices, and systems that involve photons—the elementary quanta of light. In practice, photonics encompasses the generation, control, manipulation, and detection of light across a broad range of wavelengths, from ultraviolet to infrared.

Applications span communications, sensing, imaging, medicine, and manufacturing. Key photonic devices include lasers, light-emitting diodes, detectors, modulators, and waveguides. Photonic integrated circuits pack multiple optical functions onto a single chip, enabling high-bandwidth data transmission in data centers and telecommunications. Optical fibers carry information with low loss, while photonic sensors can measure temperature, chemical composition, or biological processes with high sensitivity.

Subfields include silicon photonics, quantum photonics, nonlinear optics, biophotonics, and photonic crystals. Photonic crystals are periodic dielectric structures that affect the motion of photons, creating photonic band gaps that control light propagation. Biophotonics combines photonics with biology and medicine for imaging and diagnostic technologies.

Although photonics and electronics share goals in information processing, photonics focuses on photons rather than electrons, offering advantages in bandwidth and potentially reduced heat in certain applications. The field has matured with advances in materials, nanofabrication, and optical integration, leading to widespread use in communications, sensing, and consumer electronics.

See also: photonics, photonic integrated circuit, photonic crystal.