Physics Department, Bilkent University, Cankaya, Ankara 06800, Turkey.
Opt Lett. 2010 Apr 1;35(7):959-61. doi: 10.1364/OL.35.000959.
We demonstrate generation of pulses with up to 4 microJ energy at 1 MHz repetition rate through nonlinear chirped-pulse amplification in an entirely fiber-integrated amplifier, seeded by a fiber oscillator. The peak power and the estimated nonlinear phase shift of the amplified pulses are as much as 57 kW and 22pi, respectively. The shortest compressed pulse duration of 140 fs is obtained for 3.1 microJ of uncompressed amplifier output energy at 18pi of nonlinear phase shift. At 4 microJ of energy, the nonlinear phase shift is 22pi and compression leads to 170-fs-long pulses. Numerical simulations are utilized to model the experiments and identify the limitations. Amplification is ultimately limited by the onset of Raman amplification of the longer edge of the spectrum with an uncompressible phase profile.
我们通过完全集成光纤的放大器中的非线性啁啾脉冲放大，在 1MHz 重复率下展示了最高 4μJ 能量的脉冲生成，其种子来自光纤振荡器。放大脉冲的峰值功率和估计的非线性相移分别高达 57kW 和 22pi。在 18pi 的非线性相移下，对于 3.1μJ 的未压缩放大器输出能量，获得了最短的 140fs 压缩脉冲持续时间。在 4μJ 的能量下，非线性相移为 22pi，压缩导致 170fs 长的脉冲。数值模拟用于模拟实验并确定限制因素。放大最终受到具有不可压缩相位分布的较长光谱边缘的拉曼放大的开始限制。
