X-ray scattering measurements of dissociation-induced metallization of dynamically compressed deuterium

摘要: Hydrogen, the simplest element in universe, has a surprisingly complex phase diagram. Because of applications to planetary science, inertial confinement fusion and fundamental physics, its high-pressure properties have been subject intense study over past two decades. While sophisticated static experiments probed hydrogen's structure at ever higher pressures, studies examining higher-temperature regime using dynamic compression mostly limited optical measurement techniques. Here we present spectrally resolved x-ray scattering measurements from plasmons dynamically compressed deuterium. Combined with Compton scattering, velocity interferometry determine shock pressure mass density, this allows us extract ionization state as function compression. The onset occurs close where density functional theory-molecular dynamics (DFT-MD) simulations show molecular dissociation, suggesting hydrogen transitions insulating fluid conducting without passing through an intermediate atomic phase.