Open AccessFew-cycle fs-pumped NOPA with passive ultrabroadband spectral shaping
Author(s) -
Issa Tamer,
Marco Hellwing,
Yasmina Azamoum,
Marco Hornung,
Sebastian Keppler,
Frank Schorcht,
Joachim Hein,
Malte C. Kaluza
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.388344
Subject(s) - supercontinuum , optics , laser , femtosecond , optical parametric amplifier , ultrashort pulse , chirped pulse amplification , physics , materials science , amplifier , optical amplifier , wavelength , optoelectronics , photonic crystal fiber , cmos
A compact, femtosecond-pumped noncollinear optical parametric amplifier (NOPA) is presented with a passive spectral shaping technique, employed to produce a flat-top-like ultrabroadband output spectrum. The NOPA is pumped by a dedicated 2 mJ, 120 fs Yb 3+ -based CPA system, which generates both the second harmonic pump pulse and white light supercontinuum as the signal pulse. A chirped mirror pair pre-compensates the material GVD within the optical path of the signal pulse to produce a near-FTL pulse duration at the OPA crystal output. By optimizing both the pump/signal cross angle and the pump/signal delay, the 40 cm × 40 cm footprint, single-pass, fs-pumped, direct NOPA (non-NOPCPA) system generates a record 20 µJ, 11 fs pulses at 820 nm central wavelength with a bandwidth of 230 nm FWHM, to be used as an ultrashort optical probe pulse for relativistic laser-plasma interactions at the petawatt-class POLARIS laser system.