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Detecting the full photoemission cone from laser-based ARPES experiments by leveraging deflector technology

Gauthier, Nicolas [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:000000016147243X)·Frimpong, Benson Kwaku [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)]·Armanno, Dario [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS); McGill Univ., Montreal, QC (Canada)] (ORCID:0009000061842533)·Jabed, Akib [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0009000929320351)·Goto, Francesco [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000209485951)·Hasse, Vicky [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany)]·Felser, Claudia [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany)] (ORCID:0000000282002063)·Gu, Genda [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000298863255)·Ibrahim, Heide [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000163718501)·Légaré, Francois [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000230657156)·Boschini, Fabio [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS); Univ. of British Columbia, Vancouver, BC (Canada)] (ORCID:0000000335039389)
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Abstract

Angle-resolved photoemission spectroscopy (ARPES) provides a direct access to the electronic band structure of solid and molecular systems. The momentum range accessible by this technique depends directly on the photon energy used, and low-photon-energy sources are insufficient to photoemit electrons over the full Brillouin zone of most quantum materials. In addition, while electrons are emitted over a 2π solid angle, conventional hemispherical analyzers only collect a small subset of those electrons. A previous work [Gauthier et al., Rev. Sci. Instrum. 92, 123907 (2021)] demonstrated that electrons emitted over a larger field-of-view can be acquired in one fixed configuration by accelerating them toward the analyzer with a bias voltage. Here, in this study, we extend this work by leveraging the deflector technology of novel ARPES hemispherical analyzers. We demonstrate the ability to detect all 2π photoemitted electrons in a fixed configuration for various materials, such as gold, cuprates, and transition-metal dichalcogenides. This approach is especially advantageous for time-resolved ARPES, as electron dynamics over a large momentum range can be accessed with identical measurement conditions.

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Gauthier, Nicolas [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:000000016147243X), Frimpong, Benson Kwaku [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)], Armanno, Dario [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS); McGill Univ., Montreal, QC (Canada)] (ORCID:0009000061842533), Jabed, Akib [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0009000929320351), Goto, Francesco [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000209485951), Hasse, Vicky [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany)], Felser, Claudia [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany)] (ORCID:0000000282002063), Gu, Genda [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000298863255), Ibrahim, Heide [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000163718501), Légaré, Francois [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS)] (ORCID:0000000230657156), Boschini, Fabio [Institut National de la Recherche Scientifique – Énergie Matériaux Télécommunications (INRS-EMT), Varennes, QC (Canada). Advanced Laser Light Source (ALLS); Univ. of British Columbia, Vancouver, BC (Canada)] (ORCID:0000000335039389). 2026-06-01. Detecting the full photoemission cone from laser-based ARPES experiments by leveraging deflector technology. https://doi.org/10.1063/5.0324156

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