Light beats

PuseyPN (1974) In Cummings HZ, Pike ER (eds) Photon Correlation and Light Beating Spectroscopy. Plenum Press, New York, 387... 

Cummins, H. Z., Pike, E. R. (eds.) Photon correlation and light beating spectroscopy. Proc. NATO A.S.I., Series B Physics, Vol. 3. New York Plenum 1974... 

Application of this technique to measurements of the spectral distribution of tight scattered from a pure SF fluid at its critical point was present by Ford and Benedek The scattering is produced by entropy fluctuations which decay very slowly in the critical region. Therefore the spectrum of the scattered light is extremely narrow (10 - lO cps) and can only be observed by this light beating technique 240a)... 

Cummins, H. Z., Pike, E. R. (eds.) Photon correlation and light beating spectroscopy. 

E R Pike and H Z.Cummins (eds), Photon Correlation and Light Beating spectroscopy. Plenum, New York, 1974... 

Quasi-elastic laser light scattering (also called intensity fluctuation spectroscopy, light-beating spectroscopy or photon correlation spectroscopy) is an accurate method to measure the translational diffusion coefficients of macromolecules. The diffusion coefficient is a parameter, that depends on the size and shape of the macromolecules and on the thermodynamic and hydrodynamic interaction between the macromolecules. 

Because of relaxation of surface elevations, the scattered light has a broadened spectral distribution compared with the incident light. The broadening is too small to be analyzed by the conventional Fabry-Perot interferometry," however, so the more recent technique of light beating" must be used. We call this technique intensity fluctuation spectroscopy (IFS). 

Further discussion of polydisperse solutions is given in Section 8.10 in connection with light-beating experiments. 

Photon C orrelation and Light Beating Spectroscopy, H.Z. Cu mmins and E.R. Pike Eds. (Plenum, New York, 1973). 

Photon Correlation and Light Beating Spectroscopy, H. Z. Cummins,... 

The literature [61,63-82] r rs to QELS by many differoit names, some of which are spediic methods of implemratation. The.se include dynamic light scattering, laser scattering, laser Doppler velocimeby, intensity fluctuation spectroscopy, photon correlation spectroscopy (PCS), light beating spectroscopy and homo- and heterodyne spectroscopy. Most of the techniques discussed here are based on PCS. 

Equation (7.68) reveals that the power spectrum has a peak at co = 0 [5(ct) = 0) = 1], giving the dc part 2(/). The first term e/7i) i) represents the shot-noise term, and the third term describes a Lorentzian frequency distribution peaked at co = 0 with the total power (2l7ty) i). This represents the light-beating spectrum, which gives information on the intensity profile I (co) of the incident light wave. 

H.Z. Cummins, H.L. Swinney, Light beating spectroscopy. Progress in Optics, vol. 8 (North-HoUand, Amsterdam, 1970), p. 134... 

Pike E.R., 1974, in Photon correlation and light beating spectroscopy, cds. II.Z. Cummins and E.R. Pike (Plenum Press, New York, London). 

The field is thus sometimes called light beating qtectroscopy or intensity fluctuatiou spectroscopy, li also goes by the iiaiite of dynamic liglit scallcriug. In the absence of a reference beam it is called "self-beating" spectroscopy and... 

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