Title :
Insulator to Conductor Transition in Shock Compressed Dielectrics at Multimbar Pressure
Author_Institution :
Lawrence Livermore Nat. Lab., CA
Abstract :
Summary form only given. A new generation of materials experiments at high pressures-densities-temperatures is now possible due to a variety of high energy density (HED) facilities and new compression techniques. These facilities will be used over the next decade to measure equation of state and transport properties of materials at multi-gigabar pressure and over 10 fold compression. I will describe recent experiments where high energy lasers were used to measure high pressure shock equation of state and transport properties of a few low Z materials (C, H2O, SiO2) from kbar to 10´s of Mbar. In general, with increasing shock pressure these materials transition from an insulator to an electronic conductor. In some materials, like diamond, this transition is coincident with the expected melt transition. In other materials, the onset of conductivity is either determined by chemistry (i.e. SiO2) or thermal activation of carriers across a band gap (H2O)
Keywords :
carbon; dielectric materials; electrical conductivity transitions; equations of state; high-pressure effects; hydrogen compounds; shock wave effects; silicon compounds; C; H2O; SiO2; band gap; equation of state; high energy density facilities; insulator-conductor transition; melt transition; shock compressed dielectrics; transport properties; Conducting materials; Conductors; Dielectric materials; Dielectric measurements; Dielectrics and electrical insulation; Electric shock; Equations; Laser transitions; Optical materials; Pressure measurement;
Conference_Titel :
Plasma Science, 2005. ICOPS '05. IEEE Conference Record - Abstracts. IEEE International Conference on
Conference_Location :
Monterey, CA
Print_ISBN :
0-7803-9300-7
DOI :
10.1109/PLASMA.2005.359135