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We have recently carried out exploratory dynamic experiments where the samples were subjected to prescribed thermodynamic paths. In typical dynamic compression experiments, the samples are thermodynamically limited to the principal Hugoniot or quasi-isentrope. With recent developments in a functionally graded material impactor, we can prescribe and shape the applied pressure profile with similarly shaped, nonmonotonic impedance profile in the impactor. Previously inaccessible thermodynamic states beyond the quasi-isentropes and Hugoniot can now be reached in dynamic experiments with these impactors. In the light gas gun experiments on copper reported here, we recorded the particle velocities of the Cu–LiF interfaces and have employed hydrodynamic simulations to relate them to the thermodynamic phase diagram. Peak pressures for these experiments are on the order of megabars, and the time scales range from nanoseconds to several microseconds. The strain rates of these quasi-isentropic experiments are approximately 104–106s−1 in samples with thicknesses of up to 5mm. Though developed at a light gas gun facility, such shaped pressure profiles are also feasible using laser ablation or magnetically driven compression techniques and allow for previously unexplored directions to be taken in high pressure physics.

Superconducting Au‐YBa2Cu3O7 composites have been fabricated over a Au volume fraction range of 0–100%. Microstructure measurement indicates that Au and YBa2Cu3O7 form well‐separated phases. The superconducting transition temperature Tc was found unaffected by the presence of Au. The composites exhibit low normal state resistivity and much improved ductility. The results suggest that Au is an excellent metal host for making ultrafine YBa2Cu3O7 granular solids.

Superconducting YBa2Cu3O7 thin films have been prepared by using a magnetron sputtering system in the single‐source mode. Samples deposited on [100] single‐crystal MgO with and without a Au buffer layer all show high transition temperatures (82–87 K). The use of a Au buffer layer significantly improves the superconducting properties, particularly the Meissner effect and critical current density (3.3×106 A/cm2 at T=2 K and 3.5×104 A/cm2 at T=77 K). The Au films remain metallic after high‐temperature annealing in an oxygen atmosphere. We propose to use Au buffer layers as current shunts to protect superconducting films and devices.