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We present the development of a multi-resolution photoemission spectroscopy (MRPES) setup, which probes quantum materials in energy, momentum, space, and time. This versatile setup integrates three light sources in one photoemission setup and can conveniently switch between traditional angle-resolved photoemission spectroscopy (ARPES), time-resolved ARPES (trARPES), and micrometer-scale spatially resolved ARPES. It provides a first-time all-in-one solution to achieve an energy resolution of <4 meV, a time resolution of <35 fs, and a spatial resolution of ∼10 μm in photoemission spectroscopy. Remarkably, we obtain the shortest time resolution among the trARPES setups using solid-state nonlinear crystals for frequency upconversion. Furthermore, this MRPES setup is integrated with a shadow-mask assisted molecular beam epitaxy system, which transforms the traditional photoemission spectroscopy into a quantum device characterization instrument. We demonstrate the functionalities of this novel quantum material testbed using FeSe/SrTiO thin films and MnBiTe magnetic topological insulators.
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http://dx.doi.org/10.1063/5.0072979 | DOI Listing |
Inorg Chem
September 2025
Laboratoire de Chimie Physique Matière et Rayonnement (LCPMR), CNRS UMR 7614, Sorbonne Université (SU), 4 place Jussieu, Paris 75005, France.
The one-photon KV X-ray photoelectron spectra of Na and its hydrated clusters [Na(HO)] ( = 1-6) are dominated by the unusual 1s → 1s3s transition. KV spectroscopy also reveals a pronounced redistribution of the 1s → 1s3p transition cross sections, directly correlated with hydration number and molecular arrangement. Its intrinsic two-step nature, involving simultaneous core ionization and core excitation, enables detailed investigation of solvation-induced electronic structure changes, including dipole-forbidden excitations, core-valence charge transfer, and subtle 1s → V energy shifts.
View Article and Find Full Text PDFDiscov Nano
September 2025
Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Integrated Circuit, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou, 450052, China.
A cost-effective and large-scale method for synthesizing ZnCoO nanoflowers with surface oxygen vacancies as electrode materials for supercapacitors is presented. The existence of oxygen vacancies on the surface of the ZnCoO nanoflowers has been confirmed through X-ray photoelectron spectroscopy (XPS). The energy bands and density of states (DOS) of ZnCoO are examined using density functional theory, revealing that treatment with NaBH reduces the band gap of ZnCoO while increasing the DOS near the Fermi level compared to pristine ZnCoO.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, London WC1H 0AJ, U.K.
The exceptional performance of ceria (CeO) in catalysis and energy conversion is fundamentally governed by its defect chemistry, particularly oxygen vacancies. The formation of each oxygen vacancy (V) is assumed to be compensated by two localized electrons on cations (Ce). Here, we show by combining theory with experiment that while this 1 V: 2Ce ratio accounts for the global charge compensation, it does not apply at the local scale, particularly in nanoparticles.
View Article and Find Full Text PDFNanoscale
September 2025
St. Petersburg State University, 199034 St. Petersburg, Russia.
Using angle-resolved photoemission spectroscopy (ARPES) with spin resolution, scanning tunneling microscopy/spectroscopy (STM/STS) and density functional theory (DFT) methods, we study the electronic structure of graphene-covered and bare Au/Co(0001) systems and reveal intriguing features, arising from the ferrimagnetic order in graphene and the underlying gold monolayer. In particular, a spin-polarized Dirac-cone-like state, intrinsically related to the induced magnetization of Au, was discovered at point. We have obtained a good agreement between experiment and theory for bare and graphene-covered Au/Co(0001) and have proven that both Au ferrimagnetism and the Dirac-cone-like band are intimately linked to the triangular loop dislocations present at the Au/Co interface.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Surface Science Laboratory, Department of Materials and Geosciences, Technical University of Darmstadt, Peter-Grünberg-Straße 4, 64287 Darmstadt, Germany.
The performance of NiO-based electrocatalysts for the oxygen evolution reaction (OER) is strongly influenced by the interface between the metal support (current collector) and the catalyst layer, which modulates electronic properties and electrochemical activity. This study systematically investigates the solid-solid interface behavior of NiO thin films prepared by reactive magnetron sputtering on Pt, Au, and Ni, followed by electrochemical characterization. Stepwise NiO deposition and X-ray photoelectron spectroscopy reveal distinct band alignment and electronic structure differences at the metal-catalyst interface.
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