Opt Express. 2023 Feb 27;31(5):8864-8874. doi: 10.1364/OE.484443.
We numerically demonstrate highly efficient mid-infrared quasi-parametric chirped-pulse amplification (QPCPA) based on a recently developed Sm-doped LaGaNbO (Sm:LGN) crystal. At pump wavelength around 1 µm, the broadband absorption of Sm on idler pulses can enable QPCPA for femtosecond signal pulses centered at 3.5 or 5 µm, with a conversion efficiency approaching the quantum limit. Due to suppression of back conversion, such mid-infrared QPCPA exhibits robustness against phase-mismatch and pump-intensity variation. The Sm:LGN-based QPCPA will provide an efficient approach for converting currently well-developed intense laser pulses at 1 µm to mid-infrared ultrashort pulses.
我们通过数值方法证明了基于最近开发的掺钐镓铌酸（Sm:LGN）晶体的高效率中红外准参量啁啾脉冲放大（QPCPA）。在大约 1μm 的泵浦波长下，闲频光上的 Sm 的宽带吸收可以使中心波长为 3.5μm 或 5μm 的飞秒信号脉冲进行 QPCPA，转换效率接近量子极限。由于抑制了后向转换，这种中红外 QPCPA 对相位失谐和泵浦强度变化具有很强的稳定性。基于 Sm:LGN 的 QPCPA 将为将目前在 1μm 处发展良好的强激光脉冲转换为中红外超短脉冲提供一种有效的方法。
