Nanobeam

Nanobeam refers to a nanoscale beam, a slender structural element whose cross-section typically ranges from tens to hundreds of nanometers and whose length can reach several micrometers. Nanobeams are central components in nanotechnology and nanoelectromechanical systems (NEMS) because of their high stiffness-to-mass ratio and ability to support high-frequency mechanical motion. They can be fabricated from silicon, silicon nitride, other semiconductors, or carbon-based materials, using top-down patterning (such as electron-beam lithography) followed by dry etching and a release step to free the beam.

Common forms include cantilever and doubly-clamped nanobeams, as well as optical or photonic nanobeams that integrate light confinement along their length, enabling coupling between mechanical motion and optical modes.

Mechanical properties of nanobeams depend on material and geometry; resonant frequencies typically span from hundreds of kilohertz to several gigahertz, with quality factors that can be high in vacuum but are reduced by air damping and surface losses. Surface effects and residual stress from fabrication can influence performance and long-term stability.

Applications include sensitive mass and force detection, chemical and biological sensing via shifts in resonance, and optomechanical devices where mechanical motion modulates optical signals. Nanobeam photonic cavities are used for compact light confinement and integration with other photonic components.

See also nanowire, nanobeam cavity, nanoelectromechanical system.