Electric field of the scattered light

The polarization of the incident beam is denoted by subscripts v, h, or u for vertically polarized, horizontally polarized, or nonpolarized light, respectively. Generally, the Rayleigh constant can be considered to consist of two components, and R, corresponding to the vertical and horizontal directions of the electrical field of the scattered light (Figure 5.70). Therefore, we can define six quantities R, R, R, R, and Rf, the values of which provide information about the size,... 

This quantity plays an important role in much of what follows. In fact, as we shall see, what is sometimes measured in light scattering is the spectral density of the electric field of the scattered light. Let us dwell for a moment on some properties of these functions. Fourier inversion of Eq. (2.4.1) leads to an expression for the time-correlation function in terms of the spectral density. 

The electric field of the scattered light depends strongly on the polarisations of the incoming i and outgoing f light beams with respect to the temporally varying dielectric tensor e r,t) [60] ... 

The photodetector detects the total amplitude of the radiation scattered by different monomers. The total electric field of the scattered light is E i + Es2 + + E. Before adding all of them, we first consider the sum of E, and... 

The foregoing result is quite general. If Et(0 is the electric field of a scattered light wave, if the filter is an interferometer, grating or prism (all of which are narrow-band filters), and if the detector is a photomultiplier (all photomultipliers are square-law detectors), then according to Eq. (2.4.13) the output is... 

In normal Raman scattering, a molecule is excited to a virtual state, which corresponds to a quantum level related to the electron-cloud distortion created by the electric field of the incident light. A virtual state does not correspond to a real eigenstate (vibrational or electronic energy level) of the molecule, but rather is a sum over all eigenstates of the molecule. 

When a beam of light is incident upon a molecule, it can be either absorbed or scattered. Scattering can be either elastic or inelastic. The electric field of the incident light induces a dipole moment, P, in the molecule, given by... 

The essentials of the Raman scattering experiment are shown in Figure 1. An intense monochromatic light beam impinges on the sample. The electric field of the incident radiation distorts the electron clouds that make up the chemical bonds in the sample, storing some energy. When the field reverses as the wave passes, the... 

Raman spectroscopy is an inelastic light scattering experiment for which the intensity depends on the amplitude of the polarizability variation associated with the molecular vibration under consideration. The polarizability variation is represented by a second-rank tensor, oiXyZ, the Raman tensor. Information about orientation arises because the intensity of the scattered light depends on the orientation of the Raman tensor with respect to the polarization directions of the electric fields of the incident and scattered light. Like IR spectroscopy, Raman... 

The advantage of Raman spectromicroscopy is that very small specimens can be studied while still allowing the determination of the second and fourth moments of the ODF. However, the expressions for the Raman intensities are more complex since the optical effects induced by the microscope objective have to be considered. Although the corrections may be small, they are not necessarily negligible [59]. This problem was first treated by Turrell [59-61] and later by Sourisseau and coworkers [5]. Turrell has mathematically quantified the depolarization of the incident electric field in the focal plane of the objective and the collection efficiency of the scattered light by high numerical aperture objectives. For brevity, only the main results of the calculations will be presented. Readers interested in more details are referred to book chapters and reviews of Turrell or Sourisseau [5,59,61]. The intensity in Raman spectromicroscopy is given by [59-61]... 

Figure 9.6 Experimental setup for measuring the angular distribution of the scattered light at different temperatures and externally applied electric fields. L is a He-Ne-laser, A/2 a half-wave retarder plate, P a Glan-Thomson prism, BS a beam splitter, PDl and PD2 are photodiodes and HV the high voltage amplifier. The sbn sample with 0.66 mol% Cerium is placed on a stack of Peltier-elements to control the temperature.

When light intercepts an obstacle it will be scattered, and measurement of the amplitude and polarization properties of the scattered light at various angles relative to the incident beam can provide important structural and dynamic information about a material. Figure 4.1 describes the basic light scattering experiment. Incident light with an electric field E-... 

Photon Correlation. Particles suspended in a fluid undergo Brownian motion due to collisions with the liquid molecules. This random motion results in scattering and Doppler broadening of the frequency of the scattered light. Experimentally, it is more accurate to measure the autocorrelation function in the time domain than measuring the power spectrum in the frequency domain. The normalized electric field autocorrelation function g(t) for a suspension of monodisperse particles or droplets is given by ... 

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