Jones R Jason, Moll Kevin D, Thorpe Michael J, Ye Jun
JILA, National Institute of Standards and Technology and University of Colorado, Boulder, 80309-0440, USA.
Phys Rev Lett. 2005 May 20;94(19):193201. doi: 10.1103/PhysRevLett.94.193201.
We demonstrate the generation of phase-coherent frequency combs in the vacuum utraviolet spectral region. The output from a mode-locked laser is stabilized to a femtosecond enhancement cavity with a gas jet at the intracavity focus. The resulting high-peak power of the intracavity pulse enables efficient high-harmonic generation by utilizing the full repetition rate of the laser. Optical-heterodyne-based measurements reveal that the coherent frequency comb structure of the original laser is fully preserved in the high-harmonic generation process. These results open the door for precision frequency metrology at extreme ultraviolet wavelengths and permit the efficient generation of phase-coherent high-order harmonics using only a standard laser oscillator without active amplification of single pulses.
我们展示了在真空紫外光谱区域产生相位相干频率梳。锁模激光器的输出被稳定到一个飞秒增强腔，腔内焦点处有气体喷流。腔内脉冲产生的高峰值功率通过利用激光器的全重复率实现了高效的高次谐波产生。基于光学外差的测量表明，原始激光器的相干频率梳结构在高次谐波产生过程中得到了完全保留。这些结果为极紫外波长的精密频率计量打开了大门，并允许仅使用标准激光振荡器高效地产生相位相干的高阶谐波，而无需对单个脉冲进行有源放大。
