Parratt

Parratt is a surname of English origin. It is borne by various people and has entered scientific literature as an eponym for a calculation method used in thin-film analysis.

Parratt formalism: The Parratt formalism, or Parratt recursion method, is used to model the specular reflectivity of X-rays or neutrons from multilayer structures. The method treats each layer as a medium with a given complex refractive index and thickness and computes reflection and transmission amplitudes recursively, starting at the substrate and moving outward. It can incorporate interfacial roughness and is widely used in X-ray reflectometry, neutron reflectometry, and the characterization of thin-film coatings and multilayer mirrors.

History: The technique was developed by L. G. Parratt in 1954 and has since become a standard tool in surface and interface science.

Other uses: In general, Parratt is a surname found in English-speaking contexts and may refer to various individuals across fields such as academia, sports, and public life. The name's occurrence reflects its distribution in genealogical and biographical records.