Laser polarization

Fig. 2.6.6 Remotely reconstructed high field NMR images of laser-polarized 129Xe gas in the hollow CAL pores. Owing to the flow pattern where the spins have to flow around two corners [see the probe design in...

R. W. Mair, R. Wang, M. S. Rosen, D. Candela, D. G. Cory, R. L. Walsworth 2003, (Applications of controlled-flow laser-polarized xenon gas to porous and granular media study), Magn. Reson. Imag. 21, 287. 

Gian laser polarizer in the 365-nm beam path. The so-called parallel and perpendicular polarizations are referenced to the ion TOF axis. 

Fig. 9. The translational energy distributions of H2O photodissociation at 121 nm obtained with photolysis laser polarization parallel to the detection direction, (a) The upper trace was acquired experimentally, (b) The lower trace is the simulated distribution.

CM) frame of 0cm relative to the photolysis laser polarization can be represented by the following formula ... 

Fig. 14. The product translational energy distributions at very low translational energy region. The solid lines are the experimental results while the dotted lines are the simulated distributions, (a) The photolysis laser polarization is perpendicular to the detection axis, (b) the photolysis laser polarization is parallel to the detection axis.

Fig. 15. The product translational energy distributions for the OH + D channel from the HOD photodissociation at 121.6 nm with the photolysis laser polarization parallel as well as perpendicular to the detection direction.

Fig. 2. The inverse Abel transform of the 0(1D2) photofragment images with both laser polarizations vertical and in the plane of the paper. The dissociation wavelength is shown for each image, but each image is arbitrarily scaled in size. The atoms were ionized via the 205.4 nm (2 + 1) REMPI process.

Since we use the laser geometry where both lasers are parallel and in the plane of the detector, the resultant 3D distributions are cylindrically symmetric about the laser polarization, and thus the angular distribution can be characterized by the single variable qj. When plotting the full angular distribution 1(0a) = P(u)[l + / P2(cos0d)]/deteCtion(0difference between the shapes of the m,j =0 and rrij = 2... 

Fig. 7. Image of O2(a 1A, v = 0) recorded with both laser polarizations parallel to the image and in the vertical direction.

Figure 29 compares the calculated40 and experimental photoelectron spectra. Figure 29(a) compares the calculated spectrum from the ground state of HsO with the experimental spectrum that was obtained with a zero angle between the laser polarization and direction of electron detection,... 

Recently, an interesting correlation between the laser pulse polarization and the ellipticity of the electron beam profile has been observed [71]. However, no major influence of laser polarization on the efficiency of the electron acceleration processes has been observed so far, nor this influence has been predicted by theory and simulations, differently from the proton acceleration. For proton acceleration, a great improvement on bunch charge and quality are expected by using circularly polarized laser pulses focused on thin foils at ultra-high intensities [72-74]. 

Fig. 10.10. Dependence of the maximum proton energy on the laser polarization for a 13 pm mylar target in UHC conditions in the BWD (left) and in the FWD (right) direction, and 2D PIC simulations results for p and s polarization. The dashed line represents Fmax oc p x y/cos(29)2...

The WGM laser mode structure is determined by the droplet size and shape (which can be influenced by optical trapping forces26), laser polarization, and dye concentration. ... 

Another very informative nonlinear experiment involves a typical pump-probe technique, but with varying laser polarization. These experiments, again for isolated chromophores, measure the rotational anisotropy TCF [122]... 

FIGURE 63. 129Xe MAS NMR spectra of laser-polarized 129Xe adsorbed on Cco (a) and C70 (b), measured at 150 K. Note that the sharp signals at 0 ppm due to gaseous 129Xe are clipped to enlarge the scale. Reproduced by permission of Elsevier Science B. V. from Reference 70... 

Pines and coworkers70 showed the feasibility of spin polarization transfer by SPINOE from laser-polarized 129Xe to surface 13C nuclei on low surface area materials in high-resolution solid-state NMR experiments. This technique provides the basis for novel surface 13C NMR investigations, e.g. of surface coatings, supported catalysts and electrode materials. 

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