The Evolution of free Electron Density during the Interaction between Femtosecond Pulse and Lithium Niobate Crystal

摘要

The nonlinear ionization process was discussed in detail induced by femtosecond pulse in Lithum Niobate (LN) crystal. The MPI provides "seed" electrons for avalanche ionization process, and avalanche becomes significant when the density of electron created by MPI over 1020 cm-3. Recombination process leads to an obvious drop of electron density and then a dynamic equilibrium is achieved between the generation of electron and the recombination process, and the density is dependent on the incoming field.