Photonics optics

The synthesis of materials for device applications has very different requirements. Here, the most important questions are What does the device do and what factors will affect its performance The magnitude of the desired optical nonlinearity will always be one of many criteria that will ultimately dictate the material of choice. In many instances the magnitude of the nonlinearity will not be the most important parameter. Depending on the device applications, other considerations such as optical transparency, processability, one- and two-photon optical stability, thermal stability, orientational stability, and speed of nonlinear response will all be important. Our current understanding of NLO materials suggests that these variables are frequently interrelated and that there is often no ideal NLO material. The material of preference for a given application will typically be one that is the best compromise for a variety of variables. Tutorials by G. Stegeman and R. Zanoni, and by R. Lytel outline some of the NLO device applications and the related materials issues. 

Despite these difficulties, mesoscale self-assembly of inorganic materials holds promise. In fact, it is believed that the importance of self-assembly in the manufacturing of electronics, photonics, optics, and robotics mesoscale components could conceivably supersede its importance in the molecular and nanoscale sciences. Some hybrid organic—inorganic systems have attracted attention because... 

D. Day, M. Gu, and A. Smallridge, Two-Photon Optical Storage in Photorefractive Polymers in the Near-Infrared Spectral Range. In Infrared Holography for Optical Communications, Techniques, Materials, and Devices, Vol. 86 P. Boffi, D. Piccini, and M. C. Ubaldi, Eds., Springer-Verlag, Berlin, 2003, p. 75. 

Quantum errors. A quantum computer can never be regarded as perfectly isolated in all the experimental setups which have been considered (optical photon, optical cavity quantum electrodynamics, ion traps, NMR,... 

Day D, Gu M, Smallridge A. Two-photon optical storage in photorefractive polymers in the near-infrared spectral range. In Infrared holography for optical communications. Topics in apphed physics, vol. 86. Berlin Springer-Verlag 2002. p. 75-90. 

The second factor in (2.66) describes quite generally the transition probability for all possible two-photon transitions such as Raman scattering or two-photon absorption and emission. Figure 2.30 illustrates schematically three different two-photon processes. The important point is that the same selection rules are valid for all these two-photon processes. Equation (2.66) reveals that both matrix elements D,- and Dkf must be nonzero to give a nonvanishing transition probability A,/. This means that two-photon transitions can only be observed between two states i) and I/) that are both connected to intermediate levels fe) by allowed single-photon optical transitions. Because the selection rule for single-photon transitions demands that the levels i) and A ) or A ) and /) have opposite parity, the two levels i) and I/) connected by a two-photon transition must have the same parity. In atomic two-photon spectroscopy s s or s d transitions are allowed, and in diatomic homonuclear molecules Eg Eg transitions are allowed. 

A. Huber, B. Gross, M. Weitz, Th.W. Hansch, Two-photon optical Ramsey spectroscopy of the 1S-2S transition in atomic hydrogen. Phys. Rev. A 58, R2631 (1998) ... 

Kothari, N.C., and Kobayashi, T., "Single beam two-photon optical bistability in a submicron size Fabry-Perot cavity," IEEE Journal of Quantum Electronics QE-20 418 (1984). 

Coherent anti-Stokes Raman scattering (CARS) is one of several four-photon optical phenomena that can occur when a sample is exposed to two intense laser beams with frequencies coi, a>2. Some of the other phenomena, two of which are shown in Fig. 11.4, are the harmonic generation and frequency-summing... 

P. Y. Amnon Yariv, Photonics Optical Electronics in Modern Communications. New York Oxford University Press, 2007. 

R.G. Beausoleil, T.W. Hansch Two-photon optical Ramsey spectroscopy of freely falling atoms. Opt. Lett. 10, 547 (1985)... 

R.G. Beausoieil, T.W. Hansch Ultra-high-resolution two-photon optical Ramsey spectroscopy of an atomic fountain. Phys. Rev. A 33, 1661 (1986) M. A. Kasevich, E. Riis, S. Chu, R.G. DeVoe RF spectroscopy in an atomic fountain. Phys. Rev. Lett. 63, 612 (1989)... 

One would like to draw quantitative conclusions about the relative abundances of the conformations from the sizes of the peaks in Fig. 2 (upper trace), but this is xmjustifiable for several reasons. For one thing, the one-photon optical absorption strengths of the different peaks as calculated quantum-mechanicaUy do not correspond accurately to the effective multiphoton absorption cross sections appropriate to the IRMPD process [8]. For another, as clearly demonstrated by Prell et al. [48] among others, the time course of IRMPD dissociation can differ widely for different... 

Apart from the energies, computing electronic oscillator strengths, f, provides information about the relative intensity of the different transitions, initially for those states allowed in one-photon (optical) spectroscopy. Group theory indicates that one-photon allowed transitions of the molecule are those in which the direct product of the symmetries of the initial state, the corresponding dipole moment component (x, y or z), and the final state belong to the totally symmetric irreducible representation of the point group of the molecule ... 

A rapidly growing interest in nanometal fluorides emerged from their attractive perspectives in application areas such as catalysis, optics, photonics, optical amplifiers, optoceramics, composite materials, biosensing, and biolabeling. This increasing interest in new nanofluoride-based materials is clearly evidenced by the number of publications published in the past... 

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