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The repetitive-pulsed non-chain HF lasers initiated by e-beams and fast discharges were studied respectively.The e-beam initiated HF laser characterized by an all-solid-state generator was developed.A large area repetitive uniform e-beam was obtained and the Faraday cup was used to diagnose the uniformity of e-beam into the laser gas cell.The output characteristics of the laser were studied and the maximal energy of 4.8 mJ was obtained with gas mixture C2H6∶SF6=0.035.The e-beam initiated HF laser could operate at the repetition rate of 30 Hz.The discharge initiated non-chain HF laser was designed by using the technologies of peaking capacitor and UV pre-ionizing.The discharge characteristics and stability of SF6 gas in repetition mode were studied.The results show that the discharge includes main discharge(volume discharge) and arc discharge,between which the voltage maintains and no evident discharge is visible.The maximal output energy of 600 mJ is achieved under the condition of 28 kV charging voltage and 12 kPa gas pressure with 8% C2H6.Specific output energy of 8.5 J/l and laser electrical efficiency of 2.5% are obtained.In repetition mode,the laser can operate in the repetition rate from 1 Hz to 50 Hz.The first pulse energy is above 500 mJ,and the stable output energy of the laser at the repetition rate of 10 Hz is about 200 mJ.

An optical pumping source by segmented surface discharge on a Al2O3 ceramic substrate was developed to reliaze the pulse repetitive stability of surface discharge.The discharge jitter and the deviation of radiation intensity were investigated in detail under different conditions.The experimental results show that the discharge jitter mainly depends on the charging voltage,trigger pulse voltage and the distance of discharge gap,and the pulse repetition rate has a little influence on the discharge jitter in the range of 1 to 10 Hz.Furthermore,the deviation of radiation intensity mainly depends on charging voltage,and does not be affected by the pulse repetition rate and gas pressure.Normally,the discharge jitter can be less than 30 ns,and the deviation of radiaion intensity is below 2%.Research results indicate that the optical pumping source has good discharge stability.

The investigations of the XeF laser bumped by ultraviolet radiation have been studied for more than 20 years in Northwest Institute of Nuclear Technology (NINT Xi’an China). Up to now, several XeF laser devices were developed and an integrative experimental system has been set up which is comprised of a laser device, an electrical power supply, a high voltage trigger generator and a mixture gas supply device. Many key technologies were studied in detail and have been applied now. These technologies include section surface discharge, XeF2 photodissociation, synchronal trigger generating, double-sides optical pumping from opposite directions, active mixture gases supplying in real time, gases circulation, and so on. The XeF laser system operating on pulse repetition frequency (PRF) is up to 10 Hz. Two kinds of operating modes were applied. For the open gas flowing mode, the pulse energy of 3.2 J and the average power of 32 W at 10Hz is obtained. For the gases circumrotate mode, the average energy of 20 laser pulses is more than 0.5J.

A high-density gas jet supersonic nozzle is reported in this paper. The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respectively. The jitter time of the nozzle is within 10 μs with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle, the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation, which reveals the existence of the gas jet and the relative gas density evolving with time. Consequently the gas density is estimated to be well above 1019 cm−3, compared with theoretical simulations from the nozzle parameters.

A new rectangular pulse trigger generator has been developed which can generate two 10 kV pulses with a risetime less than 1 ns, a jitter of 0.2 ns and a width of about 10 ns and 40 ns, respectively. This generator uses two polymer-foil switches and 25 ohm Blumlein transmission lines composed of two-parallel standard coaxial cables discharging into two 50 ohm output cables. The pulse width and the delay between two pulses can be adjusted by changing the length of the cables.

A 20 kV, 1 ns risetime pulsed electron beam source was developed using an extremely small gap (0.1 mm) diode driven by a sub-nanosecond risetime, 10 kV rectangular pulse generator. A beam current of 5 A was detected by using a fast response Faraday cup at a distance of 2 cm away from a grid anode. The shot to shot variation of the electron beam pulse was less than 10%.

With a comparatively simple design, a wavelength tunable optically pumped XeF(C–A) laser with narrow linewidth is set up. Experiments are performed under different conditions to narrow the linewidth of the XeF(C–A) laser to the range of 0.2–1 nm, with an output energy of higher than 2 J in the spectral range of 460–500 nm. The wavelength of the XeF(C–A) laser can be tuned in the spectral range of 448–518 nm.