Optical Science & Applications: Chinese scientists develop 177 nm vacuum UV laser

If the VUV laser can be focused into a small beam point, it could be used to study mesoscopic materials and structures and make nanoobjects more precise.

To achieve this, Chinese scientists have invented a 177-nanometer VUV laser system that can obtain submicron focal points at long focal lengths. The system can be reconfigured for low-cost angle-resolved photoemission spectra and may advance condensed matter physics research.

In a study published in Light Science & Applications, researchers have developed a 177 nm VUV laser-scanning photoemission microscope system using a band plate without spherical aberration, which has a focal spot of <1μm at a long focal length (~45 mm).

Based on this microscope, they also built an off-axis fluorescence detection platform that demonstrated superior ability to reveal subtle features of materials than conventional laser systems.

Compared to current DUV laser sources with spatial resolution for ARPES, the 177 nm VUV laser source can help ARPES measurements cover a larger momentum space with better energy resolution.

The VUV laser system has an ultra-long focal length (~45 mm), sub-micron spatial resolution (~760 nm), ultra-high energy resolution (~0.3 meV) and ultra-high brightness (~355 MWM-2). It can be directly applied to photoelectric emission electron microscope (PEEM), Angle resolved photoelectron spectrometer (ARPES), deep ultraviolet laser Raman spectrometer and other scientific research instruments.

At present, the system has been connected to the ARPES of the University of Shanghai for Science and Technology, and has revealed the fine band characteristics of various new quantum materials, such as quasi one-dimensional topological superconductor TaSe3, magnetic topological insulators (MnBi2Te4)(Bi2Te3) M family, etc.

The paper links：https://www.nature.com/articles/s41377-021-00463-3 

Compiled by the Qianzhan Economist's APP Information group 

Source: www.qianzhan.com