Zaugg Christian A, Klenner Alexander, Mangold Mario, Mayer Aline S, Link Sandro M, Emaury Florian, Golling Matthias, Gini Emilio, Saraceno Clara J, Tilma Bauke W, Keller Ursula
Opt Express. 2014 Jun 30;22(13):16445-55. doi: 10.1364/OE.22.016445.
We present a 1.75-GHz self-referenceable frequency comb from a vertical external-cavity surface-emitting laser (VECSEL) passively modelocked with a semiconductor saturable absorber mirror (SESAM). The VECSEL delivers 231-fs pulses with an average power of 100 mW and is optimized for stable and reliable operation. The optical spectrum was centered around 1038 nm and nearly transform-limited with a full width half maximum (FWHM) bandwidth of 5.5 nm. The pulses were first amplified to an average power of 5.5 W using a backward-pumped Yb-doped double-clad large mode area (LMA) fiber and then compressed to 85 fs with 2.2 W of average power with a passive LMA fiber and transmission gratings. Subsequently, we launched the pulses into a highly nonlinear photonic crystal fiber (PCF) and generated a coherent octave-spanning supercontinuum (SC). We then detected the carrier-envelope offset (CEO) frequency (f(CEO)) beat note using a standard f-to-2f-interferometer. The f(CEO) exhibits a signal-to-noise ratio of 17 dB in a 100-kHz resolution bandwidth and a FWHM of ≈10 MHz. To our knowledge, this is the first report on the detection of the f(CEO) from a semiconductor laser, opening the door to fully stabilized compact frequency combs based on modelocked semiconductor disk lasers.
我们展示了一种由垂直外腔面发射激光器（VECSEL）产生的1.75吉赫兹自参考频率梳，该VECSEL通过半导体可饱和吸收镜（SESAM）进行被动锁模。该VECSEL输出231飞秒脉冲，平均功率为100毫瓦，并针对稳定可靠运行进行了优化。光谱中心位于1038纳米左右，近乎变换极限，半高全宽（FWHM）带宽为5.5纳米。脉冲首先使用后向泵浦的掺镱双包层大模面积（LMA）光纤放大至平均功率5.5瓦，然后使用无源LMA光纤和透射光栅压缩至85飞秒，平均功率为2.2瓦。随后，我们将脉冲注入高非线性光子晶体光纤（PCF）并产生了相干的倍频程超连续谱（SC）。然后，我们使用标准的f - 2f干涉仪检测载波包络偏移（CEO）频率（f(CEO)）拍频。在100千赫兹分辨率带宽下，f(CEO)的信噪比为17分贝，半高全宽约为10兆赫兹。据我们所知，这是关于从半导体激光器检测f(CEO)的首次报道，为基于锁模半导体盘激光器的完全稳定的紧凑型频率梳打开了大门。
