Gianella Michele, Nataraj Akshay, Tuzson Béla, Jouy Pierre, Kapsalidis Filippos, Beck Mattias, Mangold Markus, Hugi Andreas, Faist Jérôme, Emmenegger Lukas
Opt Express. 2020 Mar 2;28(5):6197-6208. doi: 10.1364/OE.379790.
We present gapless, high-resolution absorption and dispersion spectra obtained with quantum cascade laser frequency combs covering 55 cm. Using phase-sensitive dual comb design, the comb lines are gradually swept over 10 GHz, corresponding to the free spectral range of the laser devices, by applying a current modulation. We show that with interleaving the spectral point spacing is reduced by more than four orders of magnitude over the full spectral span of the frequency comb. The potential of this technique for high-precision gas sensing is illustrated by measuring the low pressure (107 hPa) absorption and dispersion spectra of methane spanning the range of 1170 cm - 1225 cm with a resolution of 0.001 cm.
我们展示了利用覆盖55厘米的量子级联激光频率梳获得的无间隙、高分辨率吸收光谱和色散光谱。采用相敏双梳设计，通过施加电流调制，梳状谱线在10吉赫兹范围内逐渐扫描，这对应于激光器件的自由光谱范围。我们表明，通过交织，在频率梳的整个光谱范围内，光谱点间距减小了四个多数量级以上。通过测量分辨率为0.001厘米、范围为1170厘米至1225厘米的甲烷低压（107百帕）吸收光谱和色散光谱，说明了该技术在高精度气体传感方面的潜力。
