A Study of Spectral Energetic Properties of Extreme Ultraviolet-Boosted Photo-Ionization for Precise In-Situ Measurement of an Intense Laser Pulse

摘要

Ultrashort intense laser has a promising future in nano science and nano technology because of its extreme features in time domain and super high energy density for pump/probe research and machining. Study shows that an intense few-cycle laser pulse leaves a clear fingerprint of its field envelope on the photoelectron energy spectrum as it passes through a gas involving a continuous extreme ultraviolet (xuv) radiation. The spectrum resulting from the xuv photoionization processes includes significant quantum enhancement and strong interference between photoelectron wave packets and exhibits interesting and useful energetic properties. The spectral cut-off energies sensitively reflect the strength of the laser field modulation on the photoelectron's energy, pulse duration, and interference. The linear relationships between the spectral energetic properties and the laser parameters (intensity, carrier-envelope phase, pulse-duration, and spatial profile) suggest new methods for precise intense laser pulse measurement in-situ. These methods have the advantages of predicted accuracy (at 0.1% level in the intensity), simplicity, speed, and large dynamic ranges (up to many orders of intensity).