论文标题
从自由电子激光器的两色泵探针实验的自由电子激光器的单个红外脉冲倾斜
Cavity-Dumping a Single Infrared Pulse from a Free-Electron Laser for Two-Color Pump-Probe Experiments
论文作者
论文摘要
中部至远红外光谱范围内的电磁辐射代表了研究固体和分子中多种类型的集体激发的必不可少的工具。但是，在此THZ光谱范围内的短而强烈的脉冲很难获得。虽然自由电子激光器很容易提供宽的波长感应性，但在Microjoules的顺序上，单个脉冲的能量相对中等。在这里，我们演示了一种使用自由电子激光器的空腔倾斜的设置，以在中部至远红外频率范围内提供单一的皮秒长脉冲。傅立叶量脉冲的持续时间可以因腔功能而变化，并且其能量显示超过100μj。使用上述红外脉冲作为泵，我们已经实现了磁化动力学的两种泵探针设置促进了单发时间分辨的成像。我们首先在热诱导的电磁和GDFECO薄膜的磁切换中首先证明了设置的功能，其次是通过显示单次时间分辨的检测磁性石榴石中磁化强度的共振语音转换的检测。
Electromagnetic radiation in the mid- to far-infrared spectral range represents an indispensable tool for the study of numerous types of collective excitations in solids and molecules. Short and intense pulses in this THz spectral range are, however, difficult to obtain. While wide wavelength-tunability is easily provided by free-electron lasers, the energies of individual pulses are relatively moderate, on the order of microjoules. Here we demonstrate a setup that uses cavity-dumping of a free-electron laser to provide single, picosecond-long pulses in the mid- to far-infrared frequency range. The duration of the Fourier-limited pulses can be varied by cavity detuning, and their energy was shown to exceed 100 μJ. Using the aforementioned infrared pulse as a pump, we have realized a two-color pump-probe setup facilitating single-shot time-resolved imaging of magnetization dynamics. We demonstrate the capabilities of the setup first on thermally-induced demagnetization and magnetic switching of a GdFeCo thin film and second by showing a single-shot time-resolved detection of resonant phononic switching of the magnetization in a magnetic garnet.
