Radiation, electromagnetic coherent

Conventional sources of electromagnetic radiation are incoherent, which means that the waves associated with any two photons of the same wavelength are, in general, out-of-phase and have a random phase relation with each other. Laser radiation, however, has both spatial and temporal coherence, which gives it special importance for many applications. 

Interferometric Raman spectroscopy Interferometric Raman Spectroscopy is a measurement technique that utilizes time-domain or space-domain measurements of electromagnetic radiation or other type of radiation for collecting Raman spectra based on the coherence of a radiative source. An example is a Fourier transform (FT) Raman spectrometer. 

A wide variety of four-wave-mixing processes are important in the generation of laser-like beams of electromagnetic radiation and also in phase-coherent interrogation of the structural and dynamical properties of molecules. Since three beams of radiation, each with its own frequency, propagation direction, and polarization state, are combined to generate a fourth beam,... 

Even when the wavelength of the electromagnetic radiation is small relative to the length of the bulk molecular sample, it is often necessary to think of the matter ->radiation interaction in terms of a bulk polarization induced by the radiation and detected via one or more coherence terms of the sample polarization (Mukamel, 1995). When the wavelength is small relative to sample size,... 

Interferometry is a process in which the superposition of two or more waves (beams) of sufficiently coherent electromagnetic radiation provides information about the waves and/or their differences. 

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