Internal diffraction

X-ray diffraction photographs were recorded on flat film using a camera with pinhole collination (250 ym diam.) and Ni-filtered Cu Ko radiation. Calcite (characteristic spacing 0.3035 nm) was used as an internal diffraction calibration. Interplanar spacings were measured off the original photographs and the unit cell dimensions were refined, where possible, by a least-squares procedure. 

Fig. 10.7 Field dependence of (a) the optical gain and linear absorption of a DMNPAA, PVK, ECZ, TNF composite (reprinted with permission from Nature, Meerholz et al., 1994 copyright 1994 Macmillan Magazines Limited), and (b) internal diffraction efficiency and ellipsometric transmission of a DMNPAA, PVK, ECZ composite (reproduced with permission of Wiley-VCH from Bittner et al., 1999).

Koperski and Czajkowski [02Kop2] have probed the repulsive part of the ground state, above and below the dissociation energy. They have observed the dispersed fluorescence of the Dl( ll) = 7 g —> AO" and A0 = 4 —> AO decays after selective excitation of the indicated upper vibronic states. Partly resolved n = 8 —> 0" = 0,1,2,3,4,5 discrete patterns could be recorded while the v = 7 v" and o = 4 —> v" signals remained unresolved. The accompanying bound-free frequency regions displayed Condon Internal Diffraction (CID) patterns, o +l relative maxima were observed in all cases refleeting the squared wave function, of the initial state o. ... 

Kaminov IP, Weber H P and Chandross E A, Poly(methyl methacrylate) dye laser with internal diffraction grating resonator , Appl. Phys. Lett., 1971,18, 497-9. 

Inorganic organic hybrid polymer dispersed liquid crystalline nanocomposites are reported as suitable candidate for fahricatirHi of photorefractive medium. Winiarz et al. reported one such photorefractive medium which consists of hole transporting polymer composite matrix, electro-opticaUy active nanodroplets of liquid crystal and Cadmium sulphide quantum dots as photosentizers (Winiarz and Prasad 2002). They employed poly(methylmethacrylate) (PMMA) as polymer matrix, N-ethylcarbazole (ECZ) as hole transporting medium and commercial nematic liquid crystal mixture TL 202 for fabrication of the photorefractive medium with Cadmium sulphide as photosentizer. The reported medium exhibits more than 90 % internal diffraction efficiency which is relatively high compared with other PDLC photorefractive medium. 

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