A vacuum ultraviolet laser with a submicrometer spot for spatially resolved photoemission spectroscopy

• 作者: Yuanhao Mao Dong Zhao Shen Yan Hongjia Zhang Juan Li Kai Han Xiaojun Xu Chuan Guo Lexian Yang Chaofan Zhang Kun Huang Yulin Chen
• 来源期刊: 光：科学与应用（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: Articles
• 页码范围: 371-378
• 页数: 8页
• 语种: 英文

摘要

Vacuum ultraviolet (VUV) lasers have demonstrated great potential as the light source for various spectroscopies,which, if they can be focused into a small beam spot, will not only allow investigation of mesoscopic materials and structures but also find application in the manufacture of nano-objects with excellent precision. In this work, we report the construction of a 177 nm VUV laser that can achieve a record-small (～0.76 μm) focal spot at a long focal length (～45 mm) by using a flat lens without spherical aberration. The size of the beam spot of this VUV laser was tested using a metal grating and exfoliated graphene flakes, and we demonstrated its application in a fluorescence spectroscopy study on pure and Tm3+-doped NaYF4 microcrystals, revealing a new emission band that cannot be observed in the traditional up-conversion process. In addition, this laser system would be an ideal light source for spatially and angle-resolved photoemission spectroscopy.