利用抽运-探测技术研究了皮秒激光脉冲诱导下Bi20Sb80(BiSb)薄膜的时间分辨反射率演化过程。利用原子力显微镜和椭圆偏振光谱仪研究了激光诱导开关前后薄膜微区的表面结构特征和光学特性。结果表明,在一定能量密度范围内的皮秒激光脉冲作用下,该薄膜具有快速光热开关特性,瞬态反射率变化的开关时间约为19 ns,且不随激光能量密度的变化而变化,在多次脉冲重复作用下具有较好的重复性和稳定性。表明BiSb薄膜有望用于超快光存储超分辨掩模结构中,这将为发展新型快速开关掩模材料和理解BiSb作为超分辨掩模的工作机理提供帮助。 The time-resolved reflectivity evolution of Bi20Sb80 (BiSb) thin films induced by picosecond laser pulses was studied by using the pump-probe technique. Atomic force microscopy and ellipsometry spectroscopy were used to study the surface structure and optical properties of the thin film before and after laser induced switching. The results show that the film has a fast photothermal switch characteristic under the picosecond laser pulse with a certain energy density. The switching time of the transient reflectance is about 19 ns and does not change with the laser energy density. Multiple pulse repetition has good repeatability and stability. Indicating that BiSb films are expected to be used in ultrafast optical memory super-resolution mask structures, which will help to develop new fast switching mask materials and understand the working mechanism of BiSb as a super-resolution mask.