Extreme self-compression of laser pulses in the self-focusing mode resistant to transverse instability

Yakovlev

et al. 2021

High Pow Laser Sci Eng

The input pulse of the laser PEARL with energy of 18 J and pulse duration of about 60 fs was compressed to 10 fs after passage through a 4-mm thick KDP crystal and reflection at two chirped mirrors with sum dispersion −200 fs 2 . The experiments were performed for the В-integral values from 5 to 19 without visible damages of the optical elements, which indicates that small-scale self-focusing is not a significant issue. It was shown that, by virtue of the low dispersion of the group velocity, the KDP crystal has some advantages over silica: a larger pulse compression coefficient, especially at a small value of the В-integral (B=5…9), lower absolute values of chirped mirror dispersion, and also a possibility to control the magnitude of nonlinearity and dispersion by changing crystal orientation.

Section: Resultsmentioning

confidence: 99%

Use of KDP crystal as a Kerr nonlinear medium for compressing PW laser pulses down to 10 fs

Shaykin

Yakovlev

et al. 2021

High Pow Laser Sci Eng

“…Third, the SSSF for laser pulses with a small number of field oscillations was investigated in [41,42]. It was shown analytically that the type of instability changes to the convective one.…”

Section: Discussion Of the Resultsmentioning

confidence: 99%

11 fs, 1.5 PW Laser with Nonlinear Pulse Compression

Laser Congress 2021 (ASSL,LAC)

Yakovlev

Kochetkov

et al. 2021

The PEARL laser output pulse with a duration of 60-70 fs was compressed to 11 fs after passing through a 5-mm thick silica plate and reflecting from two chirping mirrors with a total dispersion of -250 fs 2 . The experiments were carried out for the B-integral values up to 19 without damage of the optical elements, which indicates that small-scale self-focusing was suppressed. The results obtained show the possibility of further nonlinear compression scaling to multipetawatt power in pulses with duration commensurate with the field period.

“…Analytical expressions for the noise power gain similar to (2) cannot be obtained. In [39,40] , the development of SSSF was studied without the approximation of slowly varying amplitude. It was shown numerically that, in the case of anomalous dispersion, SSSF does not develop for laser pulses with a duration less than 10 field periods.…”

Section: (B) Substantial Reduction Of Noise Gain For Short Pulsesmentioning

confidence: 99%

Suppressing small-scale self-focusing of high-power femtosecond pulses

Martyanov

Balakin

et al. 2023

High Pow Laser Sci Eng

It was shown experimentally that for a 65-fs 17-J pulse, the effect of filamentation instability also known as small-scale self-focusing is much weaker than predicted by stationary and nonstationary theoretical models for high B-integral value. Although this discrepancy has been left unexplained at the moment, in practice no signs of filamentation may allow the breakthrough in nonlinear pulse postcompression at high laser energy.