Control and Measurement of attosecond pulses

In this paper attosecond measurement relies on a phase "gate". The phase of attosecond pulses is easily manipulated because attosecond pulses arise in an interferometric process - the interferometer formed by an electron being removed by the atom, propagating in the laser field and re-colliding with the parent ion where the interference occurs. Slightly modifying (gating) the phase of the electron along the trajectory encodes spatial and temporal information. We also introduce a method for producing transient optical elements for attosecond pulses and high harmonics. For control we use a slightly stronger, yet still very weak control beam. We produce a diffraction grating in the nonlinear medium itself and we observe the diffracted radiation