New methods of generation of ultrashort laser pulses for ranging

To reach the millimeter satellite laser ranging accuracy, the goal for nineties, new laser ranging techniques have to be applied. To increase the laser ranging precision, the application of the ultrashort laser pulses in connection with the new signal detection and processing techniques, is inevitable. The two wavelength laser ranging is one of the ways to measure the atmospheric dispersion to improve the existing atmospheric correction models and hence, to increase the overall system ranging accuracy to the desired value. We are presenting a review of several nonstandard techniques of ultrashort laser pulses generation, which may be utilized for laser ranging: compression of the nanosecond pulses using stimulated Brillouin and Raman backscattering; compression of the mode-locked pulses using Raman backscattering; passive mode-locking technique with nonlinear mirror; and passive mode-locking technique with the negative feedback

Transient stimulated Raman scattering: theory and experiments of picosecond pulse compression

SRS and SBS in gases for efficient pulse compression from few nanoseconds down to few picoseconds in a multistage system are studied numerically and compared with experimental results

Transient stimulated Raman scattering: theory and experiments of pulse shortening and phase conjugation properties

Numerical modelling of stimulated Raman scattering for pulse compression in the vsibile-NIR is presented. Comparisons are made with experimental results

Mode-locked diode-pumped Nd:YAP laser

International audienc

Mode-locked diode-pumped Nd:YAP laser

International audienc

Nonlinear mirror operation of a diode-pumped quasi-cw picosecond Nd:YAG laser

We apply the technique of nonlinear mirror (NLM) mode-locking to a pulsed diode-pumped, actively modelocked Nd:YAG laser. Either effective pulse compression or pulse amplitude control regimes are achieved, depending on the NLM configuration. Operating the NLM as a fast saturable absorber, 34 ps-long pulses are emitted in a 450 ns long train, with 0.5 mJ energy, at a maximum repetition rate of 100 Hz. Alternatively, in the pulse amplitude control regime, 100 ms-long flat trains of active mode-locking pulses are generated. In both cases, amplitude fluctuations lower than 2% (rms) were routinely obtained

Laser diode pumped Nd:YAG laser operating at an eye-safe wavelength of 1.443 µm

International audienc

High power diode-pumped picosecond Nd3+:YVO4 laser

A diode-pumped Nd3+:YVO4 laser passively mode locked by a nonlinear mirror based on second-harmonic generation has been developed. Pumping with a fiber-coupled 10-W diode array, we generated nearly diffraction limited, linearly polarized 11-ps pulses at 1064nm, with average power of 2.7 W at a 150-MHz repetition rate. Pulses as short as 7.9 ps were measured with reduced output power (1.35 W) by optimal focusing in the nonlinear crystal

Preparation and Characterization of Bragg Fibers for Delivery of Laser Radiation at 1064 nm

Bragg fibers offer new performance for transmission of high laser energies over long distances. In this paper theoretical modeling, preparation and characterization of Bragg fibers for delivery laser radiation at 1064 nm are presented. Investigated Bragg fibers consist of the fiber core with a refractive index equal to that of silica which is surrounded by three pairs of circular layers. Each pair is composed of one layer with a high and one layer with a low refractive index and characterized by a refractive-index difference around 0.03. Propagation constants and radiation losses of the fundamental mode in such a structure were calculated on the basis of waveguide optics. Preforms of the Bragg fibers were prepared by the MCVD method using germanium dioxide, phosphorous pentoxide and fluorine as silica dopants. The fibers with a diameter of 170 m were drawn from the preforms. Refractive-index profiles, angular distributions of the output power and optical losses of the prepared fibers were measured. Results of testing the fibers for delivery radiation of a pulse Nd:YAG laser at 1064 nm are also shown

Passive mode-locked Nd:YALO3 laser with GaAs nonlinear element

Self-mode-locking with GaAs nonlinear mirror was achieved in a flashlamp-pumped Nd:YALO3 laser. Active-passive ML was also studied, with improved stability. Pulses shorter than 50 ps were obtained