Kerr measurements

Figure 38 shows the XRD pattern (a) and hysteresis loop (b) of FePt C double-layered nanocomposite thin-film medium. The soft underlayer FeCoNi (111) peak and the Zl0 FePt (001) and (002) peaks are shown only in the XRD pattern. This means that the preferred crystal orientation of Tl0 FePt C nanocomposite film is successfully obtained on this SUL by nonepitaxial growth. The polar-Kerr measurement shows a square loop that is only sensitive to the top layer the Kerr effect data shown in this loop give the coercivity Hc = 8.5 kOe, nucleation field Hn = 5.65 kOe, remanence ratio S = 1, and loop slope ( at Hc) a = 3.3, respectively. 

Figure 14. Irradiation and disorder (left) long-range order parameter S as a function of the fluency for a disorder FePt (50 nm)-Pt (001) thin film (starting SKI) and particularly ordered one (starting S=0.4) and (right) Polar Kerr measurements of three irradiated CrPt3 areas with N+ ions with a fluency in the range 2xl015 -2xl016 ions/cm2.

Before discussing the Kerr measurements on the solutions, we briefly outline how the size of the polymers was obtained from viscosity and relaxation data. Two well-known expressions which are useful in interpreting these data are the Simha and Burgers equations. The Simha equation (20) relates the intrinsic viscosity of a solution of elongated ellipsoids... 

Fig. 65. (a) Spin orientations in an amorphous Gd-Co film having a composition gradient along the film thickness. Solid line and dotted line arrows denote Gd and Co spins, respectively. Thick line arrows indicate the total magnetization vectors, (b) Spin orientations in two layers at each stage of the anomalous hysteresis loop. The solid line and broken line arrows refer to Gd and Co spins, respectively. The Kerr measurements were made through the substrate interface. This side of the layer is indicated by a heavy solid line (after Esho, 1976). 

Figure 29 shows the non-uniform optical pattern on film due to mechanical birefringence with no field and the Kerr measurement after the short-circuited sample is irradiated with high-energy electrons. Whereas the peak electric field in Fig. 25 is -160 kV/cm, the peak field due to the trapped electrons in Fig. 27 is -1.5 MV/cm, which led to the spark discharge treeing pattern shown. 

The majority of existing experimental data on hyperpolarizabflities are derived from ESHG and dc-Kerr measurements (Shelton and Rice 1994). The dc-I rr effect differs from the other nonlinear optical processes as it allows for absolute measmements without the need for a reference measurement. The measured molar Kerr constant is (Shelton and Rice 1994) ... 

M. Cho, S. J. Rosenthal, N. F. Scherer, L. D. Ziegler, and G. R. Fleming, J. Chem. Phys., 96, 5033 (1992). Ultrafast Solvent Dynamics Connection between Time Resolved Fluorescence and Optical Kerr Measurements. 

Dipole moments and molar Kerr constants of phenotellurazines were measured (85ZOB846). The results suggest a significant shift of electron density from the benzene rings toward the heterocycle. 

The component y is also related to the second hyperpolarizability measured in dc-Kerr experiments... 

Robards, K, Kerr, A.F. and Pastalides, E (1988) Rancidity and its measurement in edible oils and snack foods. Rev. Analyst. 113, 213 (and references cited therein). 

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