Sub-10 fs gating of optical pulses

It is-demonstrated that ultrafast ionization of a surface layer of an originally transparent solid material, initialized by a moderate intense optical field, can be used to realize an ultrafast gate. The transition time generally is more than one order of magnitude faster than the driver pulse. It is shown that even driver pulses of the order of tens of femtoseconds are capable of switching pulses from the infrared to the vacuum ultraviolet on a sub-10 fs time scale. Thus, this is one of the fastest optical gates. It can be used for the measurement of the temporal dynamics of femtosecond pulses.