Extended Data Fig. 1: Schematic experimental setup.
From: Origin of strong-field-induced low-order harmonic generation in amorphous quartz
A strong mid-IR pump laser pulse is temporally and spatially overlapped with a NIR probe laser pulse in the volume of a SiO2 sample. After recollimation by a CaF2 lens (L1) the signals emerging from the sample are separately analyzed in the two parts of the detection unit. L1 - L4: Lenses, BS: Beam splitters, DM: Dielectric mirror (high reflectivity at 0.8 μm), PD: Photodiode, BD: Beam dump, P1, P2: prisms.
