Laser-atom interactions

RELATIVISTIC EFFECTS IN NON-LINEAR ATOM-LASER INTERACTIONS AT ULTRAHIGH INTENSITIES... 

Relativistic effects in non-linear atom-laser interactions at ultrahigh intensities 107... 

In the case of the 1S-3S transition in hydrogen and for an estimated velocity of v=3km/s, the shift is Av =l4A kHz. We can t measure the velocity distribution by observing the Doppler broadened 1S-2P transition at 121 nm with a colinear laser beam, because the production of Lyman-a radiation is very difficult. In 1991 a method to compensate or at least to measure this effect was proposed by F. Biraben [7]. The basic idea is to apply a transverse magnetic field B in the atom-laser interaction region. This field has two effects ... 

More specifically, the unique modal field profile and characteristics of the CBNL structure are advantageous for biochemical sensing applications, but also for surface emitting lasers and for studies involving strong atom-field interactions such as nonlinear optics and cavity QED. 

M. V. Korolkov, J. Manz, and G. K. Paramonov We are fully aware of the danger of using exceedingly intense IR picosecond/femto-second laser pulses for control of molecular vibrations or reactions. As a rule derived from laser interactions with atoms, the intensities should be below the Keldish limit [1],... 

Wolf, A. (1993). Laser-stimulated formation and stabilization of antihydrogen atoms. Hyperfine Interactions 76 189-201. 

Because ultracold trapped 2S atoms can interact with laser light for extended times, laser intensities as low as 100 W/cm2 are sufficient to drive the two-photon transition. Thus the primary systematic effect of the beam experiments is greatly reduced. 

We perform numerical modeling of atomic processes in various real plasmas including LHD fuel-pellet ablation and short-pulse laser interaction plasmas [21], We are developing a mixed quantum-classical code to study excited hydrogen atom formation in neutrals of back scattered protons at wall surfaces. 

Faisal FHM (1987) Theory of Multiphoton Processes. Plenum Press, New York see also Cohen-Tannoudji C, Dupont-Roc J, GrynbergG(1989) Photons and Atoms, Wiley, New York various articles on strong-field laser interaction especially by Faisal FHM. p. 27 and by Shih-I Chu p. 57 (1991) in Radiation Effects and Defects in Solids. Part 1, 122-123 Ullrich CA, Grossman UJ, Gross EKU (1994) Phys Rev Lett 74 872 Buot FA, Jensen KL (1990) Phys Rev B42 9429... 

Oscillator strengths or absorption cross sections may be obtained by applying saturation spectroscopy techniques to multistep photoionization spectroscopy. A few transitions in uranium have been studied.One of the advantages of saturation spectroscopy is that it can be applied to any one of the steps in the schemes shown in Fig. 2. The disadvantages are that the experimental requirements are severe (laser-atomic beam interaction area,-frequency,-band width and-polarization) and interpertation of the data can be complex. A detailed discussion will not be given because little application has been made to the lanthanides and actinides. We will discuss in the Autoionization section the determination of photoionization cross sections by a saturation method. 

Frequency measurements, which are amongst the most accurate measurements made, form a basis of, on the one hand, practical measurements of length as defined in terms of the SI metre for example, and on the other, determination of universal physical constants such as the Rydberg constant. Atomic physics lies at the heart of these measurements, providing the tools and methods of laser spectroscopy as well as the theory of atomic structure and atom-light interaction with which to interpret the results of measurements and relate them to other fields of physics. 

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