A high-energy self-CEP-stable OPCPA seeder using a high-average-power picosecond narrowband Yb thin-disc laser

Generating high-energy pulses in the short- to mid-wave infrared typically relies on parametric amplification, for which producing a suitable high-energy seed remains key. We introduce a compact and efficient seed-generation scheme based on a picosecond Yb thin-disk laser and anti-resonant-reflection photonic crystal fibers. This setup directly delivers 9-fs seed pulses with 40% conversion efficiency. Using intra-pulse difference-frequency mixing, we generate self-CEP-stable pulses with an energy of 100 nJ and an efficiency of up to 1%. A single-stage parametric amplifier then scales the output to 14 µJ at 2200 nm. The system demonstrates remarkable performance, with 1.15% energy stability over 30 minutes and 217 mrad CEP stability over 10 minutes. Our architecture is compact, energy- and wavelength-scalable, and uniquely provides high-energy, self-CEP-stable seeds. This makes it an ideal platform for advanced spectroscopy, nonlinear optics, and high-field applications in attoscience and plasma physics.