Eugeny Katin

Parametric amplification of chirped laser pulses at 911-nm and 1250-nm wavelengths

The analysis of tuning characteristics for parametric amplification in KD*P has shown that the application of KD*P crystals may considerably enhance the possibilities of certain optical parametric amplifiers of both terawatt and petawatt level. For instance, at pumping with a wavelength of (lambda) 3 equals 0.527 micrometers , which is most promising for the creation of such systems, the KD*P-based amplifiers may work far from the degenerate mode, e.g., at (lambda) s- 0.911 micrometers and (lambda) i-1.25 micrometers . For operation at these wavelengths there are currently master oscillator of femtosecond pulses with pulse duration of up to 30 fs. In this paper elements of the system are discussed, and their parameters are optimized.

Compensating for birefringence in active elements of solid-state lasers: novel method

It is shown that a uniaxial crystal (cut along the optical axis) placed inside a telescope may compensate for thermally induced birefringence in laser-active elements. Depolarization was reduced in an experiment by an order of magnitude.

Multicascade boradband optical parametric chirped pulse amplifier based on KD*P crystals

We have experimentally demonstrated the existence of super-broadband non-degenerated phase matching for a signal with a wavelength of 911 nm in KD*P crystal pumped with wavelength of 527nm. Parametric amplification coefficient of more than 107 in three cascades is achieved. This resulted in pulse energy 10mJ at the output of third cascade. It is shown that in the KD*P crystal chirped pulses of conventional femtosecond sources (a Ti:Sa laser at 911 nm and a Cr:forsterite laser at 1250 nm) can be amplified up to the level that ensures multipetawatt power after compression.

Laser Driver for a Photoinjector of an Electron Linear Accelerator (February 2014)

The presented laser driver for a photoinjector of an electron linear accelerator delivers 10-ps long laser pulses with the energy of 1.85 μJ at the wavelength of 262 nm. Laser pulses irradiating with the repetition rate of 10 MHz form the rectangular 800-μ s long pulse trains with 18.5-W mean power inside them. The pulse train repetition rate is 10 Hz. Short-lived absorption centers accumulating in BBO fourth-harmonic generator crystal cause significant distortion of the pulse train envelope. The envelope remains rectangular due to precompensating of these distortions in the fiber acousto-optical modulator with fast varying transmission.

Use of KD*P crystals for non-degenerated broadband optical parametric chirped pulse amplification in petawatt lasers

The problem of creating optical parametric amplifiers of femtosecond pulses up to the multiterawatt level was fiist discussed in [l, 21. In these papers, as well as in subsequent studies [3-91, only nonlinear elements made from KDP crystals, whose aperture can be as great as 30cm, were considered as nonlinear elements for final cascades of optical parametric amplifiers (OPAs). The most promising pump source is the second harmonic of a Nd:glass laser with a wavelength of 3L3=527nm. At this pumping, the KDP crystal has two serious disadvantages: it absorbs greatly at wavelengths higher than 1200nm and has maximal gain bandwidth (1000-1200~m~[l~]) at the wavelength of signal 1050-1 1 OOnm, i.e., at degenerated (or nearly degenerated) phasematching. In this wavelength range, however, it is difficult to create light sources with pulse duration of less than 50fs.

Synchronization of two Q-switched lasers with 150 ps jitter

Two Nd:YLF lasers with a pulse duration of about 2 ns have been synchronized. The duration and synchronization of two laser pulses are provided by two pairs of Pockels cells with synchronized voltage pulses. One of the Pockels cells in the first pair ensures Q switching, and the other cuts out a 2 ns pulse from the giant 20 ns pulse. In the second pair, one of the cells, driven by a two-step voltage pulse, forms a giant pulse synchronized with the pulse of the first laser, and the other cell cuts a short pulse out of it. The proposed scheme allows a rather simple and reliable synchronization of two Q-switched lasers with a jitter of 150 ps.

Synchronization of a pulsed Q-switched laser with a femtosecond laser with jitter less than 100 ps

In this report, a Nd:YLF laser with pulse duration of 2 ns, synchronized with a femtosecond laser is discussed. The pulse duration and synchronization are provided by two Pockels cells, in which voltage pulse is synchronized with the femtosecond laser by means of a special electronic unit. One Pockels cell ensures Q-switching, whereas the other cuts a shorter pulse out of a Q-switched pulse with 15ns duration. In such an approach, the requirements for jitter between a Q-switched pulse and a Q-switched pulse are not so strict and may be easily fulfilled. Experimental results presented herein show that the suggested two-step scheme of synchronization of a Q-switched laser and a cw laser with passive mode-locking may simply and reliably synchronize these lasers with jitter better than 100 ps.

Tabletop 300J 1ns Nd:Glass Laser for Pumping of a Chirped Pulse Optical Parametric Amplifier

300J-energy 1ns duration pulse has been achieved at the laser output with fill factor of 0.8. The laser have been accommodated on a single optical table. The energy efficiency of second harmonic generation is 55%.

Toward Petawatt Laser Based on Optical Parametrical Amplification: Status Quo and Perspectives

Laser power of more than 100TW (70fs, 10J) has been achieved in experiments on optical parametric amplification of femtosecond pulses in KD*P crystals. Energy conversion efficiency of optical parametric amplifier is 27%.

Front-end system for multi-petawatt laser based on non-generaive optical parametric amplification in KD*P

In a three-cascade optical parametric chirp pulse amplifier based on KD*P crystal the pulse energy was 100mJ at 911nm wavelength. Adding two more parametrical amplifiers (100mm and 300mm diameter) will result in a multipetawatt laser.