We present a novel photonic Doppler velocimetry(PDV)design for laser-driven shock-wave experiments.This PDV design is intended to provide the capability of measuring the free-surface velocity of shocked opaque materia...We present a novel photonic Doppler velocimetry(PDV)design for laser-driven shock-wave experiments.This PDV design is intended to provide the capability of measuring the free-surface velocity of shocked opaque materials in the terapascal range.We present measurements of the free-surface velocity of gold for as long as∼2 ns from the shock breakout,at pressures of up to∼7 Mbar and a free-surface velocity of 7.3 km/s with an error of∼1.5%.Such laboratory pressure conditions are achieved predominantly at high-intensity laser facilities where the only velocity diagnostic is usually line-imaging velocity interferometry for any reflector.However,that diagnostic is limited by the lower dynamic range of the streak camera(at a temporal resolution relevant to laser shock experiments)to measure the free-surface velocity of opaque materials up to pressures of only∼1 Mbar.We expect the proposed PDV design to allow the free-surface velocity of opaque materials to be measured at much higher pressures.展开更多
The laser-induced relativistic shock waves are described. The shock waves can be created directly by a high irradiance laser or indirectly by a laser acceleration of a foil that collides with a second static foil. A s...The laser-induced relativistic shock waves are described. The shock waves can be created directly by a high irradiance laser or indirectly by a laser acceleration of a foil that collides with a second static foil. A special case of interest is the creation of laser-induced fusion where the created alpha particles create a detonation wave. A novel application is suggested with the shock wave or the detonation wave to ignite a pre-compressed target. In particular, the deuterium–tritium fusion is considered. It is suggested that the collision of two laser accelerated foils might serve as a novel relativistic accelerator for bulk material collisions.展开更多
文摘We present a novel photonic Doppler velocimetry(PDV)design for laser-driven shock-wave experiments.This PDV design is intended to provide the capability of measuring the free-surface velocity of shocked opaque materials in the terapascal range.We present measurements of the free-surface velocity of gold for as long as∼2 ns from the shock breakout,at pressures of up to∼7 Mbar and a free-surface velocity of 7.3 km/s with an error of∼1.5%.Such laboratory pressure conditions are achieved predominantly at high-intensity laser facilities where the only velocity diagnostic is usually line-imaging velocity interferometry for any reflector.However,that diagnostic is limited by the lower dynamic range of the streak camera(at a temporal resolution relevant to laser shock experiments)to measure the free-surface velocity of opaque materials up to pressures of only∼1 Mbar.We expect the proposed PDV design to allow the free-surface velocity of opaque materials to be measured at much higher pressures.
文摘The laser-induced relativistic shock waves are described. The shock waves can be created directly by a high irradiance laser or indirectly by a laser acceleration of a foil that collides with a second static foil. A special case of interest is the creation of laser-induced fusion where the created alpha particles create a detonation wave. A novel application is suggested with the shock wave or the detonation wave to ignite a pre-compressed target. In particular, the deuterium–tritium fusion is considered. It is suggested that the collision of two laser accelerated foils might serve as a novel relativistic accelerator for bulk material collisions.
