Angle-resolved photoemission spectroscopy with nanoscale spatial resolution (Nano-ARPES) is a powerful tool for the investigation of electronic structures of materials and their spatial configurations. In order to capture the area of interest in Nano-ARPES measurements effectively, an optical microscope can be used to provide real space optical images as a reference. In this work, a new type of optical microscope for Nano-APRES spectrometer with a large tilt angle of ∼30 degrees and a long focal length of ∼12 mm has been designed. Large magnifications by 7 × to 20 × and a spatial resolution of 3 um have been achieved, which can effectively assist optical alignment for Nano-ARPES. In addition, the strong boundary sensitivity observed in such a tilt design demonstrates its special capability in detecting the fine features of surface coarseness.

Photoelectron spectroscopy is a powerful tool in characterizing the electronic structure of materials. To investigate the specific region of interest with high probing efficiency, in this work we propose a compact in situ microscope to assist photoelectron spectroscopy. The configuration of long objective distance of 200 mm with two-mirror reflection has been introduced. Large magnification of 5 × to 100 ×, lateral resolution of 4.08 μm, and longitudinal resolution of 4.49 μm have been achieved. Meanwhile, the testing result shows larger focal depth of this in situ optical microscope. Similar configurations could also be applied to other electronic microscopes to improve their probing capability.

Recently, one of uranium-based heavy fermion systems, UTe2, has attracted enormous attention because of its potential spin triplet superconductivity, whose superconducting properties are closely related to their compositions and states...