A terawatt hybrid laser (THL-100) system on the basis of a starting complex and a final amplifier with gaseous optically driven active media on XeF(C-A) molecules is presented. The starting complex manufactured consists of a Ti:sapphire master oscillator pumped by femtosecond pulses from a continuous laser pumped by (Verdy-8) at a wavelength of 532 nm, a femtosecond pulse stretcher, regenerative and multipass amplifiers pumped by a pulsed laser at a wavelength of 532 nm, a diffraction grating compressor and a second harmonic generator (KDP). The complex has the following output parameters of the laser beam: pulse duration is 50 fs, the energy of radiation at the second harmonic (475 nm) is 5 mJ. The complex can operate in a single pulse mode and a frequency of 10 Hz. The XeF(C-A) amplifier consists of a two high-voltage pulsed generator (linear transformer), a vacuum diode with six cold explosive-emission cathodes, a electron beam injection system, a Xe filled gas chamber-converter and a laser cell. The high-voltage generator consists of 12 transformer stages, and each of them involves eight capacitors (one is C=40 nF) and spark gaps. The capacitors can be charged up to voltage of 100 kV. E-beam in vacuum diode has the parameters in total current of 300 kA, peak voltage of 550 kV, pulse duration of e-beam power about 150 ns (FWHM). The total energies of the six 100 cm×12 cm e-beams which pass through the foil into the Xe converter are 6-7 kJ in the 150-160 ns pulse (FWHM). Pump energy cascade processes lead rapidly to the formation of Xe2*, which radiates a fraction of the deposited energy in the continuum at (172±5) nm. This VUV radiation is transmitted through CaF2 windows into the laser cell containing the mixture of XeF2 vapour and N2 buffer gas. VUV radiation makes photolysis of XeF2 molecules form XeF* excimer molecules. The active medium of the amplifier pumped by VUV radiation has 24 cm aperture and 110 cm length. The results of numerical modeling of the output parameters and first experimental results are presented in this paper. According to the modeling of the XeF(C-A) amplifier parameters and the first measurement of gain, it is shown that the maxmum output energy is 2-3 J, which means that the peak power has been up to 40-60 TW in a 50 fs pulse. Furthermore, It is very important that this laser system can provide a high temporal contrast up to 109-1010.
|Журнал||Guangxue Jingmi Gongcheng/Optics and Precision Engineering|
|Состояние||Опубликовано - фев 2011|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Electronic, Optical and Magnetic Materials