Shock-induced transformation of Al2O3 and LiF into semiconducting liquids.
Shock compression of sapphire (Al2O3) and lithium fluoride (LiF) to pressures above 5 Mbar has been observed to transform these transparent, wide band-gap insulators into partially degenerate liquid semiconductors with optical reflectivities of several percent. Reflectivities rise steadily with shock pressure up to 45% in sapphire at 20 Mbar and 20% in LiF at 13 Mbar. Using a simple model, the electron scattering length was inferred to be approximately the interatomic distance. In addition, several equation-of-state points at these pressures were measured.
Hicks
D G
DG
Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Celliers
P M
PM
Collins
G W
GW
Eggert
J H
JH
Moon
S J
SJ