**7. References**


104 Quantum Optics and Laser Experiments

The possibility of practical controlling probabilities of irradiative transitions without and with proton transfer by choosing properly the stop-band spectral position has been demonstrated. The "blue" shift of the luminescence spectrum of rhodamine 6G has been

The emission band observed near by the exciting line is most probably due to Raman scattering in substances forming photonic crystal structure. It becomes possible to be detected owing to the essential increase of radiation field caused by the slow diffuse transfer

Secondary emission of nonlinear photonic crystals under coherent and incoherent optical pumping observed within a 410 – 600 nm range has an asymmetric continual spectrum with a width of about 200 nm. The spectral intensity distribution and the intensity maximum position are dependent of the exciting radiation parameters (wavelength of excitation, degree of coherence, angle range of pumping wave vectors), of the emission detection angle, of the structure disordering degree. The emission observed is analyzed in terms of spontaneous parametric down-conversion phenomenon which occurs in spatially

This work was financially supported by National Academy of Sciences of Ukraine, the Ukrainian-Russian project No.71-02-10 "Radiation of 3D photonic crystals under optical and

Aliev, G., Golubev, V., Dukin, A., Kurdyukov, D., Medvedev, A., Pevtsov, A., Sorokin, L.,

Ambrozevich, S., Gorelik, V., Dirin, D., Vasil'ev, R., Vitukhnovsky, A., Voinov, Yu. (2009).

Bechger, L., Lodahl, P., Vos, W. (2005). Directional fluorescence spectra of laser dye in opal

Bykov, V. (1972). Spontaneous emission in a periodic structure. *Soviet Physics – JETP (Journal* 

Chayka, K., Moiseyenko, V., Mordzinski, A. (2005). Luminescence of 2,5-bis(2-

Emel'chenko, G., Gruzintsev, A., Koval'chuk, M., Masalov, V., Samarov, E., Yakimov, E.,

Cardona, M. (1975). *Light Scattering in Solids*, Springer-Verlag, Berlin

Hutchison, J. (2002). Structural, photonic band-gap, and luminescence properties of the opal-erbium composite. *Physics of the Solid State*, Vol.44, No12 (December 2002),

Optical properties of 3D photonic crystals filled with CdSe/CdS quantum dots. *Journal of Russian Laser Research*, Vol.30, No4, (July 2009), pp. 384-391, ISSN 1071-

and inverse opal photonic crystals. *Journal of Physical Chemistry B*, Vol.109, No5,

*of Theoretical and Experimental Physics)*, Vol.35, No.2, (February 1972), pp. 269-273,

benzoxazolyl)hydroquinone molecules adsorbed on copper island film. *Ukrainian Journal of Physical Optics*, Vol.5, No4 (November 2005), pp. 128-132, ISSN 1609-

Barthou, C., Zver'kova, I. (2005). Opal – ZnO nanocomposites: Structure and

observed in opal additionally infiltrated with pure glycerine.

of pump photons into sample volume.

nonuniform nonlinear medium.

pp. 2224-2231, ISSN 1063-7834

(May 2005), pp. 9980-9988

ISSN 0038-5646

**6. Acknowledgment** 

electric excitations".

2836

1833

**7. References** 

emission properties. *Semiconductors*, Vol.39, No11, (November 2005), pp. 1328-1332, ISSN 1063-7826


**0**

**6**

*Ukraine*

**the Pulsed Light Field**

and Alexey I. Voroshilo

*Institute of Applied Physics, NASU*

**Resonant Effects of Quantum Electrodynamics in**

Studying of various aspects of laser field influence on physical processes is one of the most topical problems of modern applied and fundamental physics. Scientific interest is due to numerous unknown before phenomena, which are caused by laser radiation application and make enable coming to the main point of atomic and molecular structure of matter. These phenomena are of great importance over such fields of physics as holography, fiberglass optics, telecommunications, material authority, biophysics, plasma physics, nuclear fusion and so on. The lasers which generate radiation within the range from deep infrared to ultraviolet one and even the soft X-rays region with intensities up to 1022 W/cm<sup>2</sup> inclusive are made accessible at present. The sources of laser radiation had been put into practice of modern experiment widespread owing to its unique properties. The laser physics progress is generally concentrated on ever shorter and more powerful laser pulses production and on application of the lasts into various fields of scientific studies. New experimental conditions require continual improvements in computations and development of model of external field

Influence of laser field on kinematics and cross-sections of various quantum electrodynamics (QED) processes of the both first and second orders in the fine structure constant has been an object of study over a long period of time already. The characteristic feature of electrodynamics processes of the second order in the fine-structure constant in a laser field is associated with the possibility of their nonresonant and resonant modes. At this rate resonant cross-sections of scattering of particles may exceed the corresponding ones in external field absence in several orders of magnitude. Resonant character relates to the fact that lower-order processes, such as spontaneous emission or one-photon production and annihilation of electron-positron pairs, are allowed in the field of a light wave. Therefore, within a certain range of energy and momentum values a particle in an intermediate state may fall within the mass shell. Then the considered higher-order process effectively decomposes into two consecutive lower-order processes. Occurrence of resonances in a laser field is one of

Theoretical study of QED processes in an external laser field basis on solutions of the Dirac's equation for an electron in the field of a plane electromagnetic wave namely the Volkov functions (Volkov (1935)). Also one has to use the Green function of an intermediate particle in

**1. Introduction**

description.

the fundamental problems of QED in strong fields.

Sergei P. Roshchupkin, Alexandr A. Lebed', Elena A. Padusenko

