Dmitry Victorovich Chausov

250-W average-power Nd:YAG laser with self-adaptive cavity completed by dynamic refractive-index gratings

A high average power laser oscillator with a cavity completed by a nonlinear mirror formed by refractive index gratings which accompany population gratings induced in Nd:YAG laser crystals by generating beams themselves is investigated numerically and experimentally. The role of different noise sources at the initial stage of nonlinear cavity formation is studied. The adaptation of the cavity formed by nonlinear dynamic mirrors to intracavity distortions is demonstrated. The generation of beams with average power up to 250 W, near-diffraction-limited divergence, and long coherence length has been achieved.

Formation of dynamic cavity in a self-starting high-average-power Nd:YAG laser oscillator

Self-organization of the dynamic cavity completed by holographic gratings in the novel laser oscillator was studied experimentally and numerically. A key role of the resonant grating of refractive index induced by generating beams in an Nd:YAG laser crystal was determined. Stabilization of the generated pulses and an increase in output power were achieved by use of a vibrating intracavity mirror.

NONDEGENERATE FOUR-WAVE-MIXING MEASUREMENTS OF A RESONANTLY INDUCED REFRACTIVE-INDEX GRATING IN A ND:YAG AMPLIFIER

Two optical waves (at 1064 nm) were used to resonantly induce a population grating in a flash-lamp-pumped Nd:YAG rod, and a nonresonant wave (at 1054 or 694 nm) was used to read (with a diffraction efficiency of as much as 1% or 0.3%, respectively) the refractive-index grating caused by the difference in the polarizability of the excited and the unexcited Nd ions. Comparisons of experimental results and numerical calculations gave the dependence of the ratio of the real and the imaginary parts of the resonant susceptibility of Nd:YAG at 1064 nm on the pump power.

Increase in phase-conjugate reflectivity of a holographic Nd:YAG oscillator due to resonant refractive-index grating

Abstract We have studied both experimentally and numerically the role of resonant refractive-index gratings (RIGs) in a self-pumped phase-conjugate mirror based on an Nd:YAG amplifier with nonreciprocal feedback loop. In experiment the generation of the phase-conjugating laser was delayed with respect to the recording of a holographic nonlinear mirror by an external beam. An increase in the phase-conjugate reflectivity at a delay time of about 3 μs was measured. The numerical calculation confirmed the additional contribution that the resonant RIG formed in a pumped Nd:YAG crystal because of excitation of a higher-lying level of Nd 3+ ions make to the efficiency of phase conjugation.

Self-starting 100-W-average-power laser with a self-adaptive cavity

The numerical and experimental investigation of a self- starting Nd:YAG laser oscillator with a cavity completed by population gratings induced in the laser crystal by generating beams themselves are reported. The spatio- temporal characteristics of the laser comprising three Nd:YAG amplifiers and a saturable absorber were investigated. The generation of single mode beam with an average power of as large as 100 W and high quality was achieved.

200-W-average-power Nd:YAG laser with self-adaptive cavity completed by dynamic refractive-index gratings

A high average power laser oscillator with a cavity completed by refractive index gratings that accompany population gratings induced in Nd:YAG laser crystals by generating beams themselves is investigated experimentally. The spatio-temporal self-adaptation of the cavity formed by nonlinear dynamic mirrors is studied. The possibility of compensating polarization distortions inside laser crystals is also investigated. The generation of beams with average power up to 250W, near-diffraction-limited divergence, and long coherence length is demonstrated.

Role of resonant refractive-index grating in a nonreciprocal Nd:YAG self-pumped phase conjugator

We have studied both experimentally and numerically the role of resonant refractive index gratings in a self-pumped phase conjugate mirror based on an Nd:YAG amplifier with nonreciprocal feedback loop. In experiment the generation of the phase-conjugating laser was delayed with respect to recording of a holographic nonlinear mirror by an external beam. An increase in the phase-conjugate reflectivity at a delay time of about 3 microseconds was measured. The numerical calculation confirmed the additional contribution of the resonant refractive-index grating, which is formed in the pumped Nd:YAG crystal due to excitation of a higher-lying level of Nd3+ ions, to efficiency of phase conjugation.

Self-starting laser with a nonlinear liquid crystal mirror

THe laser oscillator with a cavity completed by the refractive index grating induced by generating beams in a nematic liquid crystal cell was studied experimentally and theoretically. It is shown that both the thermal and orientational nonlinearity of the liquid crystal can provide the holographic mirror formation and the self-starting condition in the laser oscillator. The self-starting laser with the nonlinear mirror demonstrates single-longitudinal- mode generation with good quality of the beam.

High-average-power solid state lasers with a self-adaptive cavity based on a nonlinear mirror

A high average power laser oscillator with a cavity completed by a nonlinear mirror formed by refractive index gratings which accompany population gratings induced in Nd:YAG laser crystals by generating beams themselves is investigated experimentally. The spatio-temporal self- adaptation of the cavity formed by nonlinear dynamic mirrors is studied. The generation of beams with average power up to 250W, near-diffraction-limited divergence and long coherence length is demonstrated.

100-W-average-power Nd:YAG laser with adaptive cavity formed by self-induced population gratings

We report the experimental and numerical investigation of a self-starting Nd:YAG laser oscillator with cavity completed by population gratings which are induced in the laser crystal by generating beams themselves. The spatio-temporal characteristics of the laser including three Nd:YAG amplifiers and the saturable absorber (LiF:F2- or Cr4+:YAG) have been investigated. The laser oscillator with a nonlinear mirror has displayed self-adaptivity to strong thermally induced intracavity distortions. The generation of single mode beams with an average power of as large as 100 W and near-diffraction limited quality has been achieved.