Second harmonic light

Aktsipetrov O A, Baranova I M and Il inskii Y A 1986 Surface contribution to the generation of reflected second-harmonic light for centrosymmetric semiconductors Zh. Eksp. Tear. Fiz. 91 287-97 (Engl, transl. 1986 Sov. Phys. JETP 64 167-73)... 

This effect, which is in a loose sense the nonlinear analog of linear optical rotation, is based on using linearly polarized fundamental light and measuring the direction of the major axis of the ellipse that describes the state of polarization of the second-harmonic light. For a simple description of the effect, we assume that the expansion coefficients are real, as would be the case for nonresonant excitation within the electric dipole approximation.22 In this case, the second-harmonic light will also be linearly polarized in a direction characterized by the angle... 

As stated before, the coefficients /, g, and h are linear combinations of the components of the tensors yeee, y eem, and ymee. For a system with Ccc, symmetry (i.e., chiral, isotropic surface symmetry) and -polarized second-harmonic light detected in transmission, these coefficients are given by (For the complete set of equations, see previous sections.)... 

To analyze the second-order susceptibility, the symmetry of the films was first analyzed by measuring the intensities of the second-harmonic light. The sample was irradiated with polarized light from a Nd YAG laser incident at 45°, and the second-harmonic light emanating from the sample was detected while the sample was rotated around its surface normal. No variation in the second-harmonic intensity was observed as the sample was rotated, indicating... 

Figure 1. Intensity of second harmonic light (I ) produced by LB films of compound 6 as a function of layer number (N). Both the fundamental and second harmonic beams are p-polarized. The line (with slope 2) is the best fit according to the least square criterion.

Directly following the development of the optical laser, in 1961 Frankel et al. [10] reported the first observation of optical harmonics. In these experiments, the output from a pulsed ruby laser at 6943 A was passed through crystalline quartz and the second harmonic light at 3472 A was recorded on a spectrographic plate. Interest in surface SHG arose largely from the publication of Bloembergen and Pershan [11] which laid the theoretical foundation for this field. In this publication, Maxwell s equations for a nonlinear dielectric were solved given the boundary conditions of a plane interface between a linear and nonlinear medium. Implications of the nonlinear boundary theory for experimental systems and devices was noted. Ex-... 

The source S(t) = -pod2PNL(t)/dt2 corresponding to (4.22) has a component at frequency 2lo and complex amplitude S(2lo) = 4pb0u)2dE(uj)E u), which radiates an optical field at frequency 2co (wavelength Ao/2). Thus the scattered optical field has a component at the second harmonic of the incident optical field. Since the amplitude of the emitted second-harmonic light is proportional to S(2lo), its intensity is proportional to S 2uj) 2au)id I2, where I = E(uj) 2/2r/ is the intensity of the incident wave. The intensity of the second-harmonic wave is therefore proportional to d2, to 1/Ag, and to I2. Consequently, the efficiency of second-harmonic generation is proportional to / = P/A, where P is the incident power and A is the cross-sectional area. It is therefore essential that the incident wave have the... 

In this technique,27 a laser beam is directed onto a solid microcrystalline ( powder ) sample that is sometimes immersed in an index matching liquid. The emitted second harmonic light is collected, filtered, detected, and compared with a standard (usually a urea powder for the organometallic complexes measured to date). This technique is crude The magnitude of the response depends on particle size, and care must be taken in preparation of samples (e.g., sieving samples to ensure a narrow particle size range). 

Reiss has introduced a notation for combining the four microscopic variants of WRBS with field definitions defined by the m value. It might be preferable to keep the macroscopic adjustments separate from the molecular definitions. The question of the definition of the fields is related to the nature of the EFISH measurement. The essential observation is of the ratio between the intensity of second harmonic light emitted from the solution to that emitted by quartz standard. However the or-field is defined the ratio will be related to T by an equation (written schematically) of the kind,... 

S. Kielich. Second harmonic light scattering by dense, isotropic media. Acta Phys. Polonica, 33 89-104 (1968). 

S. Kielich, J. R. Lalanne, and F. B. Martin, second harmonic light scattering induced in liquids by fluctuational electric fields of quadrupolar molecules. Acta Phys. Polonica, A, 47 479 82 (1972). 

Samples of adsorbed Fe(CO)s were irradiated with either a pulsed nitrogen laser (4.5 mj/pulse, 337 nm) or a pulsed, frequency-tripled Nd YAG laser (10 mJ/pulse, 355 nm, first and second harmonic light removed). Each laser beam was expanded to cover the full... 

Kemnitz K, Bhattacharyya K, Hicks J M, Pinto G R, Eisenthal K B and Heinz T F 1986 The phase of second-harmonic light generated at an interface and its relation to absolute molecular orientation Chem. Phys. Lett. 131 285-90... 

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