Scientific biography

1973-1978. My research experience started in 1973 at the chair of Wave Processes of the Faculty of Physics of MSU, when I was a 3^rd - year MSU student. I took part in works of the research group, which was leaded by Prof. A.N.Penin and Prof. D.N.Klyshko. We studied spectroscopic applications of spontaneous parametric down-conversion (SPDC), registered two-dimensional frequency-angular spectra of SPDC and light scattering by polaritons in different non-linear crystals, such as lithium niobate, lithium tantalate, KDP, and others. We were first who observed these spectra in potassium pentaborate, lithium formate, several types of deuterated crystals, before and after ferroelectric phase transitions.

1978-1982. The main activity was concerned with a new method of absolute measurement of the spectral radiance of electromagnetic radiation. We showed experimentally the possibility to calibrate radiance using a perfectly new type of reference – zero fluctuations of electromagnetic vacuum. According to idea, proposed theoretically by Prof.D.N.Klyshko, we made this by comparing the signals of SPDC and parametric down-conversion of the radiation which was measured. We were first who proposed the experimental device – “parametric photometer”, and realized this method experimentally in 1979. Also, I studied the theoretical aspects of the method and of the involved parametric processes, and accounted the influence of absorption and reflection effects.

1982-1994. Further developing of the new SPDC-based method of quantum metrology for the absolute measurement of radiance. We achieved accuracy of few percents in calibration of IR radiation of a thermal source experimentally and revealed the ways to obtain the upper accuracy of 10^-2 %. The spatial and spectral resolution of the method was studied specially. It was shown, that vacuum fluctuations can be used as a new quantum-type absolute reference in photometry, being more precise and convenient than conventional references (black body models) for calibrating of high-temperature radiation, and radiation in IR range.

1985-1995. Study of linear and non-linear diffraction in multiple-domain crystals. We were first in 1986, who observed SPDC in quasi-synchronous conditions in periodically poled crystals. In experiments on multiple-domain crystals of lithium and barium-sodium niobate we showed, that SPDC can be used for measuring of period and orientation of domain superlattices with an accuracy better than 0.1 microns. We studied connection between the zone-folding effects for polaritons, linear diffraction for signal waves and non-linear diffraction in periodically poled crystals, and proved that all these effects lead to generation of parametric signal in quasi-synchronous directions. Anisotropic type of linear diffraction and redistribution of SPDC signal intensity due to this effect were studied in KDP crystals in ferroelectric phase.

1996-2002. Investigation of four-wave cascaded coherent light scattering by polaritons. Development of theoretical and experimental basics for spectroscopy of excited phonon polaritons. Study of cascaded four-wave mixing in periodically poled lithium niobate crystals. We have observed character distinction between dispersions of imaginary parts of dielectric function for equilibrium polaritons and for optically excited polaritons.

2000-2005. Study of polarons in pure and Mg-doped lithium niobate crystals: formation under chemical reduction, photon-induced hopping, influence on optical properties in IR range, polaron-induced variation of phonon parameters.

2003-2005. Study of non-linear parametric processes in media with spatial variation of second-order optical susceptibility. Characterization of periodically and quasi-periodically poled crystals by means of non-linear optical methods. Terahertz generation and detection in Czochralski-grown periodically poled crystals of doped lithium niobate.