Vladimir I. Pryalkin

Optical-damage-resistant LiNbO 3 :Zn crystal

Zinc doping is shown to reduce the photorefraction in LiNbO(3):Zn. The damage-resistant crystal LiNbO(3):Zn has demonstrated a conversion efficiency of approximately 50% for frequency doubling of 1.06-microm radiation. The dependence of optical characteristics on the ZnO concentration in the melt reveals a sharp change of the optical properties at the threshold concentration of 4-6 mol % Zn. The optical and nonlinear-optical data of LiNbO(3):Zn are similar to those of LiNbO(3):Mg, but the former shows better optical performance.

Optical and non-linear optical investigations in LiNbO3:Mg and LiNbO3:Zn

Abstract Zinc doping [1] similarly to magnesium doping (e.g. [2]) reduces the value of photorefraction in LiNbO3.

Photorefractive and nonlinear-optical properties of optical damage resistant LiNbO3:Zn crystals

Abstract Zinc doping reduce the photorefraction and laser induced coloration (dark trace effect) in LiNbO3. Optical properties of highly doped LiNbO3:Zn are relevant for the nonlinear optics. The damage resistant LiNbO3:Zn with [Zn] higher than 6 mol.%demonstrates the conversion efficiency of frequency doubling of Nd:YAG laser of about 50%exceeding that of LiNbO3:Mg. The low-doped LiNbO3:Zn crystals demonstrate large photorefractive sensitivity.

Parametric generation of high-peak-power femtosecond light pulses in LBO crystal

The parametric down conversion of femtosecond pulses at high intensity is discussed. An injection-locked parametric oscillator based on a nonlinear LBO crystal pumped by XeCl- and dye-laser systems is developed. The nonlinear refractive index n2 approximately equals 1.7 10-16 cm2/W and the optical surface breakdown threshold Ibr approximately equals 3.8 1013 W/cm2 of LBO crystal for approximately 400 fsec pulses were measured. The spatial dispersion of effective nonlinearity deff2/n3 for parametric amplification in LBO crystal is calculated. The design and performance of femtosecond dye- laser system and XeCl-excimer-laser system capable of producing a focused intensity in excess of 1016 W/cm2 are described.

New ferroelastic: LiNaCO3

Abstract New ferroelastic LiNaCO3 was grown as a single crystal. First observations of α-β-transition in the crystal, corresponding domain pattern, and some physical properties were performed, which are consistent with the ferroelastic nature of α-phase.

Terawatt femtosecond laser pulse temporal shaping using double-stage nonlinear optical conversion

Novel scheme providing for 7 J Nd-glass subpicosecond MultiTeraWatt laser pulse shortening down to 200 fs with intensity rise time of 100 fs for 2 order of magnitude and prepulse suppression down to quantum noise level are proposed. Non-linear optical two-stage converter consists of sequential second harmonic generator and stimulated raman scattering oscillator-amplifier.

Fast growth of acid KDP crystals and their optical quality

The influence of acidity of KDP salt solution on KDP crystal properties has been investigated. A number of crystals were grown from acid solutions in wide range of solution acidity. Optical properties of the crystals were studied. It has been found that UV absorption of KDP crystals depends on the acidity of solution.

Frequency conversion of intense femtosecond pulses: the route to enhance energy conversion efficiency

The phenomenon of phase-matching curve transformation under strong energy exchange conditions and its influence on frequency conversion of ultrashort light pulses in nonlinear crystals are discussed. The routes to increase energy conversion efficiency in three-wave interactions are suggested.