Nonlinear Generation, Compression and Spatio‐Temporal Analysis of sub‐GV/cm‐Class Femtosecond Mid‐Infrared Transients

Abstract

AbstractA Yb:YAG thin‐disk regenerative amplifier with 3 kHz repetition rate pumps a second‐order nonlinear mixing scheme providing femtosecond transients of maximum electric field strength beyond 330 MV cm−1 at a center frequency of 45 THz. This value surpasses field conditions present at submolecular dimensions of matter. The inherent competition between efficiency and bandwidth in parametric downconversion is overcome with a third‐order nonlinear step of self‐phase modulation (SPM). The high repetition rate, versatility, beam quality, and passive phase stability of our system support advanced spectroscopic approaches like electro‐optic sampling (EOS). With this technique, solitonic self‐compression and octave‐spanning supercontinua directly on a subcycle scale are studied.