Beat spectroscopy

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... 

B. A Brief Summary of Level Crossing and of Beat Spectroscopy. . 235... 

Application of Beating Spectroscopy to Molecular Weight Determinations... 

Introduction. Previously we have described the way in which beating spectroscopy may be used to obtain values of the diffusion coefficient... 

In the detection of the autocorrelation functions in self-beat spectroscopy, solution polydispersity can lead to a non-exponential form. If we assume that there are no contributions to the autocorrelation function except those from translational diffusion for the different types of molecules, we can consider two simple cases a continuous distribution of solute particle sizes and several distinct components in a solution. We shall approach the two cases by determining their effect on the observed correlation function. 

From the description presented here, it can be seen that self-beating spectroscopy as a technique for measuring the diffusion coefficient of... 

When the fine structure frequencies fall below 100 MHz they can also be measured by quantum beat spectroscopy. The basic principle of quantum beat spectroscopy is straightforward. Using a polarized pulsed laser, a coherent superposition of the two fine structure states is excited in a time short compared to the inverse of the fine structure interval. After excitation, the wavefunctions of the two fine structure levels evolve at different rates due to their different energies. For example if the nd3/2 and nd5/2 mf = 3/2 states are coherently excited from the 3p3/2 state at time t = 0, the nd wavefunction at a later time t can be written as40... 

Level crossing spectroscopy has been used by Fredriksson and Svanberg44 to measure the fine structure intervals of several alkali atoms. Level crossing spectroscopy, the Hanle effect, and quantum beat spectroscopy are intimately related. In the above description of quantum beat spectroscopy we implicitly assumed the beat frequency to be high compared to the radiative decay rate T. We show schematically in Fig. 16.11(a) the fluorescent beat signals obtained by... 

Although it might appear that this technique is in some respect surpassed by the more powerful and versatile photon correlation spectroscopy (laser beat spectroscopy) which will be discussed in a later paragraph, it can still serve as a convenient method to study the absolute scattered intensity of small colloidal particles. 

Photon-Correlation Spectroscopy (Laser-Beat Spectroscopy)... 

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

Hack, E. and Huber, J.R. (1991). Quantum beat spectroscopy of molecules, International Reviews in Physical Chemistry, 10, 287-317. 

Walther, Th., Bitto, H. and Huber, J.R. (1993). High-resolution quantum beat spectroscopy in the electronic ground state of a polyatomic molecule by IR-UV pump-probe method, Chem. Phys. 

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