Development of a 10.8-eV Tabletop Femtosecond Laser with Tunable Polarization for High-Resolution Angle-Resolved Photoemission Spectroscopy

TL;DR

This paper reports the development of a compact 10.8-eV femtosecond laser with tunable polarization, enabling high-resolution ARPES studies of quantum materials with detailed electronic and spin structure analysis.

Contribution

The authors constructed a tabletop 10.8-eV femtosecond laser with tunable polarization, high photon flux, and high energy resolution for advanced ARPES applications.

Findings

Achieved 11.8 meV energy resolution in ARPES

Demonstrated tunable polarization for orbital and spin studies

Validated system capabilities on prototypical quantum materials

Abstract

The development of extreme ultraviolet sources is critical for advancing angleresolved photoemission spectroscopy (ARPES), a powerful technique for probing the electronic structure of materials. Here, we report the construction of a tabletop 10.8-eV femtosecond laser through cascaded third-harmonic generation, which operates at a repetition rate of 1 MHz and delivers a photon flux of approximately 1012 photons/s. The system achieves a high energy resolution of approximately 11.8 meV and tunable polarization. This flexibility enables detailed studies of orbitaland (pseudo)spin characteristics in quantum materials. We demonstrate the capabilities of this laser-ARPES system by investigating several prototypical materials, showcasing its potential for elucidating complex phenomena in quantum materials.