Vogelsang Jan, Robin Jörg, Piglosiewicz Björn, Manzoni Cristian, Farinello Paolo, Melzer Stefan, Feru Philippe, Cerullo Giulio, Lienau Christoph, Groß Petra
Opt Express. 2014 Oct 20;22(21):25295-306. doi: 10.1364/OE.22.025295.
The investigation of fundamental mechanisms taking place on a femtosecond time scale is enabled by ultrafast pulsed laser sources. Here, the control of pulse duration, center wavelength, and especially the carrier-envelope phase has been shown to be of essential importance for coherent control of high harmonic generation and attosecond physics and, more recently, also for electron photoemission from metallic nanostructures. In this paper we demonstrate the realization of a source of 2-cycle laser pulses tunable between 1.2 and 2.1 μm, and with intrinsic CEP stability. The latter is guaranteed by difference frequency generation between the output pulse trains of two noncollinear optical parametric amplifier stages that share the same CEP variations. The CEP stability is better than 50 mrad over 20 minutes, when averaging over 100 pulses. We demonstrate the good CEP stability by measuring kinetic energy spectra of photoemitted electrons from a single metal nanostructure and by observing a clear variation of the electron yield with the CEP.
超快脉冲激光源能够对飞秒时间尺度上发生的基本机制进行研究。在此，脉冲持续时间、中心波长，尤其是载波包络相位的控制，已被证明对于高次谐波产生和阿秒物理的相干控制至关重要，并且最近对于金属纳米结构的电子光发射也很重要。在本文中，我们展示了一种2周期激光脉冲源的实现，其波长可在1.2至2.1μm之间调谐，并且具有固有的载波包络相位（CEP）稳定性。后者通过两个共享相同CEP变化的非共线光学参量放大器级的输出脉冲序列之间的差频产生来保证。当对100个脉冲进行平均时，在20分钟内CEP稳定性优于50毫弧度。我们通过测量单个金属纳米结构光发射电子的动能谱，并观察电子产率随CEP的明显变化，证明了良好的CEP稳定性。
