Thorn K E, Monahan N R, Prasad S K K, Chen K, Hodgkiss J M
Opt Express. 2018 Oct 15;26(21):28140-28149. doi: 10.1364/OE.26.028140.
A key requirement in the field of ultrafast vibrational spectroscopy is to efficiently generate intense tunable narrowband picosecond laser pulses synchronized to a broadband femtosecond laser source. Current nonlinear methods for picosecond pulse generation suffer from complexities in both experimental implementation and pulse frequency tunability. We present here a straightforward method for spectral bandwidth compression that produces frequency tunable picosecond pulses with efficient power conversion. Broadband femtosecond laser pulses are compressed to narrowband picosecond pulses using frequency domain sum-frequency generation of spatially chirped pulses, achieving spectral bandwidths of <20 cm and power conversion efficiency of ∼18%. The experimental design of the bandwidth compressor is presented and its application to stimulated Raman spectroscopy is demonstrated.
超快振动光谱领域的一项关键要求是有效地产生与宽带飞秒激光源同步的高强度可调谐窄带皮秒激光脉冲。目前用于产生皮秒脉冲的非线性方法在实验实施和脉冲频率可调谐性方面都存在复杂性。我们在此提出一种直接的光谱带宽压缩方法，该方法能产生具有高效功率转换的频率可调谐皮秒脉冲。利用空间啁啾脉冲的频域和频产生，将宽带飞秒激光脉冲压缩为窄带皮秒脉冲，实现了小于20厘米的光谱带宽和约18%的功率转换效率。介绍了带宽压缩器的实验设计，并展示了其在受激拉曼光谱中的应用。
