Speaker
Description
We present an interferometric field-sampling approach for characterizing few-cycle laser pulses, using photoionization of ambient air as the detection medium. Our method uses two replicas of the laser pulse to be sampled: one initiates sub-cycle ionization in air, while the delayed replica accelerates the released electrons and encodes the waveform in the resulting transient plasma current. By recording the current as a function of the interferometer delay, we retrieve the temporal structure of the near-infrared few-cycle field directly under ambient conditions. In addition to the self-referenced geometry, we characterize the few-cycle pulse itself, rather than a longer-wavelength field sampled with a separate few-cycle gate. The method thus combines self-referenced operation, broadband sensitivity, and experimental simplicity, providing a compact tool for direct waveform diagnostics in strong-field experiments.