Here, a sensitive reflection pump–probe technique is demonstrated for studying the optical nonlinear (NLO) properties of samples with a high linear absorptive coefficient at a certain wavelength. Light with a broad-angle spectrum around the Brewster angle is applied as the incident beam. An adjustable slit is utilized to select a part of the reflection angle, replacing the traditional rotation method in the reflection pump probe. The sensitivity of this technique is affected by the position and width of the slit. The closer to the Brewster angle, the more sensitivity the technique achieves. This technique can precisely control the angle of reflection, resulting in a significant enhancement with easier system operation. In addition, the simple optical path used here can be applied to other techniques for studying the properties of NLO samples. Experimentally, a normalized reflectivity enhancement is observed at 532 nm, and the impact of the incident angle on the pump-probe signal of the silicon crystal is investigated.

这里，展示了一种灵敏的反射泵浦探针技术，用于研究在特定波长下具有高线性吸收系数的样品的光学非线性（NLO）特性。具有布儒斯特角附近的广角光谱的光被用作入射光束。利用可调狭缝来选择部分反射角度，取代了反射泵浦探头中传统的旋转方法。该技术的灵敏度受狭缝的位置和宽度的影响。越接近布鲁斯特角，该技术的灵敏度就越高。该技术可以精确控制反射角度，从而显着增强系统操作性。此外，这里使用的简单光路可以应用于研究 NLO 样品特性的其他技术。实验中，在 532 nm 处观察到归一化反射率增强，并研究了入射角对硅晶体泵浦探测信号的影响。