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We study the peculiarities of the absorption spectra in D1,2-lines of Cs, caused by optical pumping in cells with antirelaxation coating. In these cells the internal state of the atom, which arose under optical pumping by a monochromatic laser field, is preserved with a high probability in a collision with the wall. As a result, the optical pumping action extends to the entire volume of the cell and to all the velocities of the atoms. This leads to the speed-dependent scanning distortions of the absorption line profile. The detected features should be considered when using laserpumped quantum magnetometers with antirelaxation-coated cells.

Short-cavity diode lasers (SCDLs) emitting at the 894-nm D1 line of caesium are developed. Low threshold currents and power consumption will make it possible to use these lasers in chip-size atomic clocks (CSACs) and magnetometers. The SCDL parameters are comparable with the parameters of surface-emitting lasers.

A system is developed which allows one to stabilise the diode laser frequency at any point in the vicinity of the cyclic D2-line transition in Rb in the interval from +40 to -150 MHz and to switch the laser frequency within this interval for ~1 ms. A method is proposed and realised for increasing the contrast of the reference sub-Doppler resonance observed in circularly polarised fields. The ultimate contrast of the resonance is estimated. This system can be used to study the anomalous light pressure force acting on atoms in an optical molasses. A magnetooptical trap for Rb atoms is described.

All-round studies of heteroepitaxial HgCdTe nanostructures (NS) growth on GaAs and Si substrates by molecular beam epitaxy have been carried out. In case of Si substrate HgCdTe NS's is very perspectives for IR detectors because of equal thermal expention coefficient with silicon read-out circuits. The problems of HgCdTe conjugations with Si at epitaxy connected with large differences in lattice mismatch and differences in chemical bonding that leads to antiphased domains. We found that the precise formation of transition layer (2 nm in thickness between Si substrates and first ZnTe buffer layer leads to growth HgCdTe NS's without antiphrasis domains. V-defects and etch pits densities are equal to 103 cm−2 and 107 cm−2 respectively. The HgCdTe/Si were used for fabrication photovoltaic 640×512 MWIR focal plane arrays. The operability for λ1/2 = 4.2 μm (77K) was over 97%. The response (Sv) and NETD were as 1,5 × 109 V/W and less 20 mK respectively. We developed the precise growth of symmetric and antisymmetric HgTe QW. We found the following effects: the presence 2D electron gas with high mobilities over 5×105 cm/V×s in doped HgTe QW, the presence @D holes and electrons in undoped HgTe QW and high sensitivity to linear and circular polarized IR and THz radiation in 6 – 400 μm region.

Narrowing of the linewidth of a diode laser was achieved by an external high-Q microcavity, which was a fused silica sphere 370 μm in diameter. Coupling of the radiation in and out, and matching to a 'whispering gallery' mode of this sphere, were ensured by the method of frustrated total internal reflection. Optical feedback was provided by the Rayleigh scattering. The width of the beat-note spectra of the investigated and reference lasers did not exceed 100 kHz.

Generalized parameters are proposed for the description of the dispersion characteristics of channel waveguides. It is shown that the use of these parameters facilitates greatly the solution of the dispersion equation and makes it possible to describe the results by a single family of curves applicable to all the modes. The usefulness of this representation is demonstrated by a calculation of the effective refractive indices, of the sequence in which modes appear, and of the range of existence of waveguides with a given number of modes. The results of these calculations are tested experimentally for LiNbO3:Ti waveguides.