Feb 03, 2021
If the vacuum ultraviolet laser can be focused into a small beam spot, it can be used to study the structure of mesoscopic materials, and make nano-objects with better precision.
In order to achieve this goal, Chinese scientists have invented a 177-nanometer VUV laser system that can achieve sub-micron focus at long focal lengths.
A research result published in "Light Science & Applications" (LightScience&Applications) shows that researchers have developed a 177nmVUV laser scanning photoelectric emission microscope system using a spherical aberration-free strip plate, which is at a long focal length (——45mm) The bottom has a focal spot of <1μm.
Compared with the DUV laser source with spatial resolution currently used for ARPES, the 177nmVUV laser source can help ARPES measurement to cover a larger momentum space and has better energy resolution.
The VUV laser system has an ultra-long focal length (-45mm), sub-micron spatial resolution (-760nm), ultra-high energy resolution (-0.3meV) and ultra-high brightness (-355MWm-2). It can be directly applied to scientific research instruments such as photoelectric emission electron microscope (PEEM), angle-resolved photoelectron spectrometer (ARPES), deep ultraviolet laser Raman spectrometer.
At present, the system has revealed the fine energy band characteristics of various new quantum materials, such as quasi-one-dimensional topological superconductor TaSe3, magnetic topological insulators (MnBi2Te4) (Bi2Te3) m family and so on.