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Updated: Jun 22, 2026
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Temperature and doping-dependent renormalization effects of the low energy electronic structure of Ba1-xKxFe2As2
A Koitzsch1, D S Inosov, D V Evtushinsky
1Institute for Solid State Research, IFW-Dresden, P.O.Box 270116, D-01171 Dresden, Germany.
Abstract:
We investigate the low energy electronic structure of Ba1-xKxFe2As2 (x=0; 0.3, T_{c}=32 K) single crystals by angle-resolved photoemission spectroscopy with a focus on the renormalization of the dispersion. A kink feature is detected at E approximately 25 meV for the doped compound which vanishes at T=200 K but stays virtually constant when T_{c} is crossed. Our experimental findings rule out the magnetic resonance mode as the origin of the kink and render conventional electron-phonon coupling unlikely. They put stringent restrictions on the dominant source of the electronic interaction channel.
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