Since 2020, aggregated from related topics
Second-harmonic generation (SHG) is a nonlinear optical process in which incoming photons interact with a nonlinear medium to generate new photons with twice the frequency (and therefore half the wavelength) of the original photons. This phenomenon is widely used in various areas of research and technology, including bioimaging, materials science, and telecommunications. SHG is particularly useful for studying the properties of materials with high spatial resolution and sensitivity, making it a valuable tool for investigating a wide range of phenomena at the nanoscale level.