Sample rotation angle

Fig. 5.10. Dependencies of the s —p SHG intensity on the sample rotation angle measured for two subsequent LP UV irradiations with orthogonal polarization directions for 40 (dots) and 90 (circles) minutes, respectively. Solid line is a fit according to reference [50].

Figure 5.12 Analyzer angle, (p versus sample rotation angle. 9 curves (experimental points) measured by transmission null eUipsometry for the optical film shown in Figure 5.11 [13]. The film is optically equal to the positive A crystal plate with a slow axis perpendicular to the polarization direction of the actinic light used in photoalignment processing. The in-plane retardation is 185.9 nm...

Figure 7 IN718 sample with segregation, SQUID-Signal versus rotation angle, scan radius is constant and equal to radial coordinate of segregation. Measurements are performed after demagnetization.

Dvinskikh SV, Castro V, Sandstrom D (2004) Heating caused by radiofrequency irradiation and sample rotation in C-13 magic angle spinning NMR studies of lipid membranes. Magn Reson Chem 42 875-881... 

In 2006 Wimperis et al. proposed a method called satellite transitions acquired in real time by MAS (STARTMAS) [142, 202], which allows for the real-time acquisition of high-resolution NMR spectra of spin-3/2 nuclei under MAS. This method combines a train of pulses, similar to CPMG [109, 110], with sample rotation at the magic angle to refocus the quadrupolar broadening in a series of echoes, while allowing the isotropic quadrupolar shift and chemical shift to evolve. 

The nonlinearity of the sample was analyzed using the experimental procedure described in Section 3.3 The polarization of the fundamental beam of a YAG laser was continuously varied by means of a quarter waveplate, and the intensity of the second-harmonic signal was measured as a function of the rotation angle of the quarter waveplate. The obtained polarization pattern were then fitted to Eq. (42), which yields the relative values of the expansion coefficients /, g, and h. The experimental results for the transmitted, glass-side-incidence, s-polarizcd signal are shown in Figure 9.20. 

Figure 9.23 s-Polarized second-harmonic signal detected in transmitted direction as function of the azimuthal rotation angle. Twofold pattern clearly indicates C2 symmetry of sample. 

It is weliknown that all static polarizations of a beam of radiation, as well as all static rotations of the axis of that beam, can be represented on a Poincare sphere [25] (Fig. la). A vector can be centered in the middle of the sphere and pointed to the underside of the surface of the sphere at a location on the surface that represents the instantaneous polarization and rotation angle of a beam. Causing that vector to trace a trajectory over time on the surface of the sphere represents a polarization modulated (and rotation modulated) beam (Fig. lb). If, then, the beam is sampled by a device at a rate that is less than the rate of modulation, the sampled output from the device will be a condensation of two components of the wave, which are continuously changing with respect to each other, into one snapshot of the wave, at one location on the surface of the sphere and one instantaneous polarization and axis rotation. Thus, from the viewpoint of a device sampling at a rate less than the modulation rate, a two-to-one mapping (over time) has occurred, which is the signature of an SU(2) field. 

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