Wave optics

Diffraction is based on wave interference, whether the wave is an electromagnetic wave (optical, x-ray, etc), or a quantum mechanical wave associated with a particle (electron, neutron, atom, etc), or any other kind of wave. To obtain infonnation about atomic positions, one exploits the interference between different scattering trajectories among atoms in a solid or at a surface, since this interference is very sensitive to differences in patii lengths and hence to relative atomic positions (see chapter B1.9). 

This wave equation is tire basis of all wave optics and defines tire fimdamental stmcture of electromagnetic tlieory witli tire scalar function U representing any of tire components of tire vector functions E and H. (Note tliat equation (C2.15.5) can be easily derived by taking tire curl of equation (C2.15.1) and equation (C2.15.2) and substituting relations (C2.15.3) and (C2.15.4) into tire results.)... 

As already mentioned, the results in Section HI are based on dispersions relations in the complex time domain. A complex time is not a new concept. It features in wave optics [28] for complex analytic signals (which is an electromagnetic field with only positive frequencies) and in nondemolition measurements performed on photons [41]. For transitions between adiabatic states (which is also discussed in this chapter), it was previously intioduced in several works [42-45]. 

Wellen-messer, m. wavemeter, ondometer, cymometer, -optik, /. wave optics. 

Kuppers, D. Schelas, K.H., Topical Meeting on Integrated and Guided Wave Optics, Th.C. 6-1 Kissimmee, USA, 198A. 

Figure 4. Diagram (w-fi) showing phase-matching scheme for guided wave optical...

Nayar, B. K. Digest 6th Topical Mtg. on Integrated and Guided Wave Optics 1982, ThA2. 

The concept of resolution in AFM is different from radiation-based microscopies because AFM imaging is a three-dimensional imaging technique. There is an important distinction between images resolved by wave optics and those resolved by scanning probe techniques. The former is limited by diffraction, whereas the latter is limited primarily by apical probe geometry and sample geometry. Usually the width of a DNA molecule is loosely used as a measure of resolution, because it has a known diameter of 2.0 nm in its B form. 

Chu, S.T. and Chaudhuri, S.K., 1989, A finite-difference time domain method for the design and analysis of guided-wave optical structures, J. Lightwave Technol. 7 2033-2038. 

Melloni, A., Morichetti, F., and Martinelli, M., 2003, Linear and nonlinear pulse propagatiou in coupled resonator slow-wave optical structures. Opt. Quantum Electron. 35 365-379. 

Yariv, A., 1973, Coupled-mode theory for guided-wave optics, IEEE J. Quantum Electron. QE-9(9) 919-933. 

To demonstrate the method an example of a slow-wave optical structure is modelled. Such structures consist of a cascade of directly coupled optical resonators in order to enhance the nonlinear effects. The structure used here was recently defined within Working Group 2 of the European Action COST Pll (http //w3.uniromal.it/energetica/slow waves.doc). One period of the structure consists of one-dimensional Fabry-Perot cavity placed between two distributed Bragg reflectors (DBR) and can be described by the sequence... 

A. Melloni, F. Morichetti, and M. Martinelli, "Linear and nonlinear pulse propagation in coupled resonator slow-wave optical structures," Opt. Quant. Electron. 35, 365-379 (2003). 

However, the theorem of reciprocity is a wave optical argument that does not consider intensities where we easily find the differences. For example, if one thinks of a STEM as an inverted HRTEM one would not detect any intensity in an image since it is an inherent property of a point detector to collect no intensity. On the other extreme side, the ability to form an intense and focused probe is a valuable ability that boosts local spectroscopy. Obviously, the best choice of tools cannot be a matter of exclusion but must relate to the problem at hand that needs solving . 

Femtosecond photoion (photoelectron) microscopy combines the merits of two types of microscopy the high spatial resolution of ion projective microscopy and the high spectral (energy) resolution of optical spectroscopy. From this point of view, photoion microscopy is an interesting example of wave-corpuscular microscopy. Indeed, there are two well-known types of microscopy wave (optical) and corpuscular (electron, ion). 

Thus, laser femtosecond pulses allow us to combine wave (optical) and corpuscular (ion electron) microscopy. This kind of microscopy is based on... 

A. Long-Wave Optical Phonons and Polaritons 1. Longitudinal Optical and Acoustical Phonons... 

This was first investigated by Huang n). Long-wave optical phonons are those with small k values. A polar phonon is an infrared-active phonon. Polar phonons therefore can only be observed in the Raman effect for crystals having no center of symmetry in the elementary cell. For centro-symmetric crystals the rule of mutual exclusion applies infrared-active phonons are forbidden in Raman scattering and vice versa. The elementary cells of NaCl and LiF have a center of symmetry, but GaP has none. The following considerations may therefore be applied to GaP as an example. This crystal has two atoms in the elementary cell and is cubic. It can be treated as an optically isotropic medium. 

A nice qualitative derivation of the Gladstone-Dale equation was given by Schoorl (1920). The Huygens-Fresnel wave optics leads to the conclusion that the refractive index is equal to the ratio of the light velocities in the two media of transmission and also to the ratio of the respective wave-lengths so Snellius law can be extended to... 

The following testing practice for continuous wave optical radiation sources as a part of explosion protected electrical apparatus has been introduced by PTB ... 

Quantum theory was developed primarily to find an explanation for the stability of atomic matter, specifically the planetary model of the hydrogen atom. In the Schrodinger formulation the correct equation was obtained by recognizing the wave-like properties of an electron. The first derivation by Schrodinger [30] was done by analogy with the relationship that was known to exist between wave optics and geometrical optics in the limit where the index of refraction, n does not change appreciably over distances of order A. This condition leads to the eikonal equation (T3.15)... 

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