| The state for material at extreme pressure and relatively low temperature is an important topic in the studies on astrophysics, fusion physics and the fundamental physics of condensed matter. One common method for obtaining such extreme state in laboratory is ramp compression, compressing the samples to high density but below their melt temperature. In recent years, a series of experimental records of pressure have been achieved by temporal-shaped laser driving technique, which has shown the great potential. More extreme states of matter will be achieved one after another. It has great significance to develop this technique in time in our country.Theoritical works, data processing techniques, ramp compression experiments, and related laser techiniques have been studied or performed in this paper. They were given as follows:1. The background, research methods, development of ramp compression, and research contents were introduced in the first chapter.2. The theories of isentropic compression and usually used state equations were introduced in the second chapter.3. An analytical isentropic compression model for condensed matter was studied and obtained based on hydrodynamic equations and a Murnaghan form state equation. Explicit solutions on loading surface and in flow fied are given. The factors influencing isentropic region width are discussed. Based on this model, pulse profile of loading pressure and driven laser are deduced, and the ramp compression simulations of aluminum are performed by the hydrodynamic code MULT ID. The process of the ramp compression is described by temperature, pressure, density, particle velocity and entropy production. Results show the primiry sucess in theory.4. Main data processing techniques or experimental design techniques are studied in this work, containing backward integration, Lagrangian analysis technique, iterative Lagrangian analysis technique, and characterisitics technique. Codes for these techniques were completed, and applications or simulations were performed. Besides, a new characteristics method for isentropic compression simulation has been developed by using a Murnaghan form isentropic equation and characteristics. It has been verified by example uses that this method can give all the detailed information of a isentropic compression flow field across impedance mismatching interfaces. Besides, this method can be operated in forward direction and backward direction. Thus it can be widely used in experimental design and experimental data processing.5. According to the analytical model we have established, quasi-isentropic compression experiments were performed on a long pulse temporal-shaped laser facility. Three target configurations were used in these experiments, which were three-step Aluminum target, CH-coated planar Aluminum target, and CH-coated three-step Aluminum target with970J,1921J, and740J laser energy respectively. Upper pressure limits were reported for the first time, which was194GPa for simple Aluminum target and645GPa for CH-coated composite Aluminum target. What’s more,425GPa peak pressure was obtained in CH-coated three-step Aluminum target, which has exceeded all the experimental results of aluminum ever reported. The strain lines agreed well to the results on OMEGA performed by R. F. Smith, a bit stiffer than the results on Z machine performed by J. P. Davis and Sesame3700isentrope line, and much slower than Sesame3700Hugoniot line. The analytical model used in experiment was proven effective, and a new ablation pressure scales with laser intensity was obtained, which was p(MBar)=0.41[IL(TW/cm2)]3/4. Besides, the problems such as weak shocks generating and streaks missing are discussed and reasonable explanations are given.
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