Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany.
Opt Lett. 2011 Nov 1;36(21):4299-301. doi: 10.1364/OL.36.004299.
We report on a low-noise diode laser oscillator at 972 nm actively stabilized to an ultrastable vibrationally and thermally compensated reference cavity. To increase the fraction of laser power in the carrier we designed a 20 cm long external cavity diode laser with an intracavity electro-optical modulator. The fractional power in the carrier reaches 99.9%, which corresponds to an rms phase noise of φ(rms)2=1 mrad2 in 10 MHz bandwidth. Using this oscillator, we recorded 1S-2S spectra in atomic hydrogen and have not observed any significant loss of the excitation efficiency due to phase noise multiplication in the three consecutive two-photon processes.
我们报告了一种工作在 972nm 的低噪声二极管激光振荡器，该振荡器通过主动稳定到一个超稳定的振动和热补偿参考腔。为了增加载波中激光功率的比例，我们设计了一个带有腔内电光调制器的 20cm 长的外腔二极管激光器。载波中的功率分数达到 99.9%，对应于 10MHz 带宽内的均方根相位噪声φ(rms)2=1mrad2。使用这个振荡器，我们记录了原子氢的 1S-2S 光谱，并且没有观察到由于在三个连续的双光子过程中的相位噪声倍增而导致的激发效率的任何显著损失。
