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Time-resolved XUV ARPES with tunable 24-33?eV laser pulses at 30?meV resolution.

ABSTRACT: High harmonic generation of ultrafast laser pulses can be used to perform angle-resolved photoemission spectroscopy (ARPES) to map the electronic band structure of materials with femtosecond time resolution. However, currently it is difficult to reach high momenta with narrow energy resolution. Here, we combine a gas phase extreme ultraviolet (XUV) femtosecond light source, an XUV monochromator, and a time-of-flight electron analyzer to develop XUV-based time-resolved ARPES. Our technique can produce tunable photon energy between 24-33?eV with an unprecedented energy resolution of 30?meV and time resolution of 200?fs. This technique enables time-, energy- and momentum-resolved investigation of the nonequilibrium dynamics of electrons in materials with a full access to their first Brillouin zone. We evaluate the performance of this setup through exemplary measurements on various quantum materials, including WTe₂, WSe₂, TiSe₂, and Bi₂Sr₂CaCu₂O_8+?.

SUBMITTER: Sie EJ

PROVIDER: S-EPMC6684652 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Time-resolved XUV ARPES with tunable 24-33 eV laser pulses at 30 meV resolution.

Sie Edbert J EJ Rohwer Timm T Lee Changmin C Gedik Nuh N

Nature communications 20190806 1

High harmonic generation of ultrafast laser pulses can be used to perform angle-resolved photoemission spectroscopy (ARPES) to map the electronic band structure of materials with femtosecond time resolution. However, currently it is difficult to reach high momenta with narrow energy resolution. Here, we combine a gas phase extreme ultraviolet (XUV) femtosecond light source, an XUV monochromator, and a time-of-flight electron analyzer to develop XUV-based time-resolved ARPES. Our technique can pr ...[more]

PMID: 31388015

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