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arXiv · 2305.14052

Laser-based angle-resolved photoemission spectroscopy with micrometer spatial resolution and detection of three-dimensional spin vector

Takuma Iwata·T. Kousa·Y. Nishioka·K. Ohwada·K. Sumida·E. Annese·M. Kakoki·Kenta Kuroda·H. Iwasawa·M. Arita·S. Kumar·A. Kimura·K. Miyamoto·T. Okuda
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Abstract

We have developed a state-of-the-art apparatus for laser-based spin- and angle-resolved photoemission spectroscopy with micrometer spatial resolution (micro-SARPES). This equipment is achieved through the combination of a high-resolution photoelectron spectrometer, a 6-eV laser with high photon flux that is focused down to a few micrometers, a high-precision sample stage control system, and a double very-low-energy-electron-diffraction spin detector. The setup achieves an energy resolution of 1.5 (5.5) meV without (with) the spin detection mode, compatible with a spatial resolution better than 10 micrometers. This enables us to probe both spatially-resolved electronic structures and vector information of spin polarization in three dimensions. The performance of micro-SARPES apparatus is demonstrated by presenting ARPES and SARPES results from topological insulators and Au photolithography patterns on a Si (001) substrate.

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Takuma Iwata, T. Kousa, Y. Nishioka, K. Ohwada, K. Sumida, E. Annese, M. Kakoki, Kenta Kuroda, H. Iwasawa, M. Arita, S. Kumar, A. Kimura, K. Miyamoto, T. Okuda. 2023-05-23. Laser-based angle-resolved photoemission spectroscopy with micrometer spatial resolution and detection of three-dimensional spin vector. https://doi.org/10.1038/s41598-023-47719-z

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