Field dependent avalanche ionization rates in dielectrics.
From the pulse length dependence of the absorption of intense ultrashort laser pulses focused inside fused silica, we reveal the role field-assisted collisional ionization plays in the multiphoton ionization process. This constitutes a cold avalanche ionization mechanism that persists at pulse lengths considered too short for a traditional avalanche.
Rajeev
P P
PP
National Research Council of Canada, Ottawa, Canada, K1A 0R6.
Gertsvolf
M
M
Corkum
P B
PB
Rayner
D M
DM