Coherent Anti-stokes Raman Spectroscopy

High Quality Content by WIKIPEDIA articles! Coherent anti-Stokes Raman spectroscopy, also called Coherent anti-Stokes Raman scattering spectroscopy (CARS), is a form of spectroscopy used primarily in chemistry, physics and related fields. It is sensitive to the same vibrational signatures of molecules as seen in Raman spectroscopy, typically the nuclear vibrations of chemical bonds. Unlike Raman spectroscopy, CARS employs multiple photons to address the molecular vibrations, and produces a signal in which the emitted waves are coherent with one another. As a result, CARS is orders of magnitude stronger than spontaneous Raman emission. CARS is a third-order nonlinear optical process involving three laser beams: a pump beam of frequency ωp, a Stokes beam of frequency ωS and a probe beam at frequency ωpr. These beams interact with the sample and generate a coherent optical signal at the anti-Stokes frequency (ωpr+ωp-ωS). The latter is resonantly enhanced when the frequency difference between the pump and the Stokes beams (ωp-ωS) coincides with the frequency of a Raman resonance, which is the basis of the technique\'s intrinsic vibrational contrast mechanism. Dannoe izdanie predstavlyaet soboj kompilyatsiyu svedenij, nahodyaschihsya v svobodnom dostupe v srede Internet v tselom, i v informatsionnom setevom resurse "Vikipediya" v chastnosti. Sobrannaya po chastotnym zaprosam ukazannoj tematiki, dannaya kompilyatsiya postroena po printsipu podbora blizkih informatsionnyh ssylok, ne imeet samostoyatelnogo syuzheta, ne soderzhit nikakih analiticheskih materialov, vyvodov, otsenok moralnogo, eticheskogo, politicheskogo, religioznogo i mirovozzrencheskogo haraktera v otnoshenii glavnoj tematiki, predstavlyaya soboj isklyuchitelno faktologicheskij material. This book was created using print-on-demand technology.