[en] The fabrication and measurement of isentropic release targets were described. The Al, Au, Ag , Cu and Zn thin foils were cut to hundred micron by apparatus of laser. They are fabricated to isentropic release targets using in the laser equation of state experiments by the assembly. The parameters of targets were measured by NT1100 profiling system. The isentropic release targets were used in 'SG Ⅱ' experiments and good images were obtained. (authors)

[en] The fabrication of metal film steps used in equation of state experiment targets was investigated. The metal film step of hundreds of microns width was cut by picosecond laser processing technology. The factors of generating heat effect in the processing were analyzed. The processing parameters were as follows: power 0.5 W, pulse width 10 ps, wavelength 355 nm, and scanning speed 100 mm/s. Two metal films of 400 and 120 microns width were obtained in the experiment. The measurement results show that the width of metal film can be precisely controlled and the quality of metal film surface before and after cutting was the same. (authors)

[en] A line velocity interferometer for any reflector has been implemented at the Shenguang-II laser facility. This instrument is the primary diagnostic for a variety of experiments involving laser-driven shock-wave propagation,materials characterization experiments and shock timing experiments. It measures velocities of interfaces, free surfaces and shock fronts traveling through transparent media. It can measure shock breakout time at temporal resolutions as low as 20 ps, and spatial resolution 10 μm. Experiments were carried out on the Shenguang-II laser facility and high quality interference images were obtained. (authors)

[en] On the basis of the three-beam output of basic frequency from 'Shenguang-II' laser facility and beam smoothing technology of lens-array, the shock wave with a better planarity in ranged 650-750 μm the target was created after optimum design and rational combination for laser beam. Then the efficiency of output beams from 'Shenguang-II' laser facility had been raised. And the shock stability experiment with the inclined-plane target indicated that the shock wave steadily propagated in the Al target of thickness of about 28.38-55.82 μm and 22.13-35.07 μm under the power density of 3.26 x 10¹⁴ W/cm² and 3.11 x 10¹⁴ W/cm² respectively

[en] Liquid hydrogen and deuterium have abundant electrical and optical properties at high pressure. A simple model to calculate the conductivity of low-Z materials was constructed. Combining the model with experiment, this paper introduces the study of the ionization and conductivity of liquid deuterium at around 70 GPa. The results show that, deuterium at this range of pressure has an ionization about 0.067%, conductivity about 2.87 × 10⁵(W·m)^-1, which means the shocked deuterium reaches a conducting state with characteristic of metallic fluid. Apparently, the transition from the insulating molecular state to metallic state of deuterium begins at a lower pressure. (authors)

[en] Measurement of shock temperature under high temperature and high pressure is an essential part of equations of state(EOS) research. This paper introduces a temperature diagnosis system for laser-driven shock wave experiment on the basis of SG-Ⅱ high-power laser facility. The system comprised the streaked optical pyrometer (SOP) which is high time-resolved and the spectral resolved SOP (SSOP). The VISAR system was added to measure emissivity. The on-line calibration system of temperature measurement was established simultaneously using a NIST traceable standard lamp. High time-resolved signal images of the high temperature radiation spectrum were obtained through experiments driven by high power laser on aluminum using the diagnosis system. The shock temperature of aluminum was obtained according to gray body radiation theoretical model. The measured temperature was 2.95 eV, which was close to Hugoniot temperature in SESAME library at the same shock wave velocity. The experiment result indicates that the temperature measurement system used in the experiment can diagnose the shock temperature of metallic materials effectively. (authors)

[en] A line-imaging optically recording velocity interferometer system (L-ORVIS) fitting the high-strain rate motion of solids as in shock wave experiments requires a high power single-mode laser. We have put forward a new illumination method which can increase threefold the luminosity of such a diagnostic. A modified illumination system is applied to the L-ORVIS which was implemented at 'Shenguang-II' laser facility. The modified L-ORVIS is applied to laser-driven shock wave experiments and platinum Hugoniots were obtained at both high pressure and low pressure

[en] With the folding target and double-step target, the propagating character of shock wave driven by an inclined-incident (with angle of ∼45 degree) laser was studied on 'Shenguang-II' high-power laser facility. The result indicated that the shock wave in the target still propagates along the vertical direction to the target surface. Also the same result was verified indirectly by another experiment based on the measurement for spatial intensity distribution of x-ray radiated from jet plasmas

[en] The first experimental investigation about the shock wave character produced and impacted by flyer have been reported, which is driven by laser and has flied a different distances shaping a special inclined cavity target with continuous variant cavity length. And the experiment about effect of increasing pressure with flyer is demonstrated and also realizes a great pressure growth more than six times

[en] In this paper, we systematically study preheating in laser-direct-drive shocks by using a velocity interferometer system for any reflector (VISAR). Using the VISAR, we measured free surface velocity histories of Al samples over time, 10–70 μm thick, driven directly by a laser at different frequencies (2ω, 3ω). Analyzing our experimental results, we concluded that the dominant preheating source was X-ray radiation. We also discussed how preheating affected the material initial density and the measurement of Hugoniot data for high-Z materials (such as Au) using impedance matching. To reduce preheating, we proposed and tested three kinds of targets