Ultrafast ion emission from metallic tip excited by femtosecond laser pulses

Using femtosecond time resolved measurements of the ion evaporation flux from a metal tip, the authors study the temporal behavior of ion emission a few femtoseconds after the incident ultrashort laser pulse. The authors show that the ultrafast response of surface electrons generates a very short and intense ion emission. Also a weak heating of the specimen was observed leading to the increase of the ion emission rate. The observed ultrafast ion emission is consistent with the model based on the rectification of the optical field at the surface of the material.