Photoemission with laser-generated harmonics tunable to 80 eV

Frequency-resolved optical gating of femtosecond pulses in the extreme ultraviolet

Femtosecond extreme ultraviolet (XUV) pulses were fully characterized for the first time by using a newly developed cross-correlation frequency-resolved optical gating (FROG) technique in the XUV region. This method utilizes laser-assisted two-photon ionization as a nonlinear optical process. Near-infrared pulses characterized by FROG were used as a reference. The amplitude and phase of XUV pulses with a pulse duration of 10 fs were found to be in good agreement with a model analysis, taking into account phase modulation by ionization, self-phase modulation, and the atomic dipole phase.

Resonance ionization image detectors: basic characteristics and potential applications

A type of spectrally selective imaging optical detector that is based on resonance ionization in an atomic vapor is proposed. It has the potential for improved spatial, spectral, and temporal resolutions compared with those of available techniques. Figures of merit are calculated and compared with those of existing techniques. Several potential applications such as the imaging of moving objects, ultrasonic fields, high-energy particle detection, and optical communications are discussed.