Spin-resolved photoelectron spectroscopy using femtosecond extreme ultraviolet light pulses from high-order harmonic generation

Journal Article · Fri Apr 15 00:00:00 EDT 2016 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4946782· OSTI ID:22597135

Plötzing, M.; Weier, C.; Plucinski, L.; Schneider, C. M. ^[1]; Eich, S.; Emmerich, S.; Rollinger, M.; Aeschlimann, M. ^[2]; Mathias, S. ^[3]

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1. Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-6), 52425 Jülich (Germany)
2. University of Kaiserslautern and Research Center OPTIMAS, 67663 Kaiserslautern (Germany)
3. Georg-August-Universität Göttingen, I. Physikalisches Institut, 37077 Göttingen (Germany)

The fundamental mechanism responsible for optically induced magnetization dynamics in ferromagnetic thin films has been under intense debate since almost two decades. Currently, numerous competing theoretical models are in strong need for a decisive experimental confirmation such as monitoring the triggered changes in the spin-dependent band structure on ultrashort time scales. Our approach explores the possibility of observing femtosecond band structure dynamics by giving access to extended parts of the Brillouin zone in a simultaneously time-, energy- and spin-resolved photoemission experiment. For this purpose, our setup uses a state-of-the-art, highly efficient spin detector and ultrashort, extreme ultraviolet light pulses created by laser-based high-order harmonic generation. In this paper, we present the setup and first spin-resolved spectra obtained with our experiment within an acquisition time short enough to allow pump-probe studies. Further, we characterize the influence of the excitation with femtosecond extreme ultraviolet pulses by comparing the results with data acquired using a continuous wave light source with similar photon energy. In addition, changes in the spectra induced by vacuum space-charge effects due to both the extreme ultraviolet probe- and near-infrared pump-pulses are studied by analyzing the resulting spectral distortions. The combination of energy resolution and electron count rate achieved in our setup confirms its suitability for spin-resolved studies of the band structure on ultrashort time scales.

• OSTI ID: 22597135
• Journal Information: Review of Scientific Instruments, Vol. 87, Issue 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BRILLOUIN ZONES
COMPARATIVE EVALUATIONS
COUNTING RATES
ELECTRONS
ENERGY RESOLUTION
EXCITATION
EXTREME ULTRAVIOLET RADIATION
HARMONIC GENERATION
LASERS
LIGHT SOURCES
MAGNETIZATION
PHOTOELECTRON SPECTROSCOPY
PHOTOEMISSION
PHOTONS
PROBES
PULSES
SPACE CHARGE
SPECTRA
SPIN
THIN FILMS