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

ABSTRACT: 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??m) 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.

SUBMITTER: Mao Y 

PROVIDER: S-EPMC7820001 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature