Georgy D. Laptev

Intracavity quasi-phase-matched self-frequency doubling and halving in periodically poled Nd:Mg:LiNbO3

We introduce the theory of intracavity quasi-phase-matched three-frequency wave interactions in active-nonlinear periodically poled medium, and in particular, self-frequency doubling and halving. The combination of laser oscillation of active ions with nonlinear optical properties of the host material provides an opportunity for creation laser with self- frequency conversion. Quasi-phase-matched second harmonic generation at 0.542 micrometer by self-frequency doubling of fundamental radiation laser radiation at 1.084 micrometer in periodically poled Nd:Mg:LiNbO3 crystal pumping by diode laser at 0.810 micrometer has been observed experimentally.

LIGHT WAVE INTERACTIONS IN ACTIVE NONLINEAR CRYSTALS WITH QUADRATIC NONLINEARITY

Recent results in the field of three-frequency wave interaction in homogeneous and inhomogeneous (periodically poled) active nonlinear crystals with quadratic nonlinearity are reviewed. The quasi-phase-matched processes of self-frequency doubling, self-frequency halving, and frequency mixing of the pump and laser radiations are studied. The consecutive quasi-phase-matched processes of the third-harmonic generation and parametric amplification with low-frequency pumping in periodically poled active nonlinear crystals are also investigated. The analysis is carried out for the case of a periodically poled Nd:Mg:LiNbO3 crystal. Perspectives of using periodically poled active nonlinear crystals in laser devices with self-frequency conversion are discussed.

Quasi-phase-matched self-frequency summing in a periodically poled Nd:Mg:LiNbO 3

We introduce the results of the study of intracavity quasi-phase-matched three-frequency wave interactions in active nonlinear periodically poled crystals. The process of self-frequency summing in periodically poled Nd:Mg:LiNbO3 has been studied. Quasi-phase-matched sum-frequency generation at 0.464 μm by self-frequency summing of fundamental radiation at 1.084 μm and unabsorbed part of pump radiation of diode laser at 0.810 μm in periodically poled Nd:Mg:LiNbO3 crystal has been realized experimentally.

Depolarization degree of diode-pumped single-frequency monolithic ring Nd3+:YAG laser

For the first time depolarization degree of the diode-pumped monolithic ring Nd3+:YAG laser has been measured. The obtained value of depolarization degree equals 3 (DOT) 10-3. It has been shown that the dominant mechanism of the intracavity losses and the output light depolarization is diffraction on random inhomogeneities of birefringence in the laser media.

Intracavity self-frequency conversion in periodically poled active nonlinear Nd:Mg:LiNbO 3 crystal

We introduce the results of the study of quasi-phase matched processes of self-frequency conversion in periodically poled active nonlinear crystals. The processes of self-frequency doubling and self-frequency summing have been experimentally realized and studied in periodically poled Nd:Mg:LiNbO3 crystals in CW and Q-switched regimes. The theory of self-frequency conversion has developed. The results of theory are in good agreement with experiments.

Spatial structure of radiation at self-frequency conversion in active nonlinear crystals

The intracavity self-frequency conversion of laser radiation in active nonlinear crystal is studied. The spatial distributions of intensities and powers of laser radiation and radiation with conversed frequency are calculated by the method of numerical simulations as functions of parameters of cavity, active nonlinear crystal and pump. The analysis is performed for periodically poled Nd:Mg:LiNbO3 crystal taking diffraction into account.

Nonclassical light generation in the process of self-frequency halving in a periodically poled active nonlinear Nd:Mg:LiNbO3 crystal

Nonclassical light generation at self-frequency halving in periodically poled active nonlinear crystals is studied. The squeezing spectra of fundamental radiation and its subharmonic are investigated for a periodically poled Nd:Mg:LiNbO3 crystal.

Simultaneous generation second and third harmonics in crystal with the modulated second-order nonlinearity

We present results of theoretical and experimental study of the consecutive third harmonic generation in a periodically poled bulk LiNbO/sub 3/:Y crystal. It is shown theoretically that under certain conditions for nonlinear coefficients the energy of wave with frequency /spl omega/ in the consecutive considered interaction can be almost completely converted to the energy of wave with frequency 3/spl omega/.

Frequency sweeping of narrowline diode-pumped microlaser radiation in multipass pulsed slab amplifier

We present results of theoretical and experimental investigations of frequency sweeping mechanisms of the narrowline diode-pumped monolithic ring Nd:YAG laser radiation in multipass pulsed slab amplifier. The obtained value of the maximal chirp in the four-pass slab amplifier does not exceed 7.7 kHz when energy of the pump pulses is 36 J and the duration of these pulses is 0.3 ms.

Spatial coherence and depolarization of radiation of diode-pumped single frequency monolithic ring Nd:YAG laser

We present results of precise measurement of spatial coherence degree and depolarization degree of the single frequency diode-pumped monolithic ring Nd:YAG laser radiation. An analysis is made of the factors influencing the spatial coherence and depolarization of miniature lasers with longitudinal diode pumping.