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arXiv · 2203.11121

Multispectral time-resolved energy-momentum microscopy using high-harmonic extreme ultraviolet radiation

Michael Heber·Nils Wind·Dmytro Kutnyakhov·Federico Pressacco·Tiberiu Arion·Friedrich Roth·Wolfgang Eberhardt·Kai Rossnagel
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Abstract

A 790-nm-driven high-harmonic generation source with a repetition rate of 6 kHz is combined with a toroidal-grating monochromator and a high-detection-efficiency photoelectron time-of-flight momentum microscope to enable time- and momentum-resolved photoemission spectroscopy over a spectral range of $23.6$-$45.5$ eV with sub-100-fs time resolution. Three-dimensional (3D) Fermi surface mapping is demonstrated on graphene-covered Ir(111) with energy and momentum resolutions of $\lesssim$$100$ meV and $\lesssim$$0.1$ $\r{A}^{-1}$, respectively. The table-top experiment sets the stage for measuring the $k_z$-dependent ultrafast dynamics of 3D electronic structure, including band structure, Fermi surface, and carrier dynamics in 3D materials as well as 3D orbital dynamics in molecular layers.

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Michael Heber, Nils Wind, Dmytro Kutnyakhov, Federico Pressacco, Tiberiu Arion, Friedrich Roth, Wolfgang Eberhardt, Kai Rossnagel. 2022-03-21. Multispectral time-resolved energy-momentum microscopy using high-harmonic extreme ultraviolet radiation. https://doi.org/10.1063/5.0091003

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