Seminaria

Dnia 2023-12-12 o godzinie 13:15 w Sali 2011 Wydziału Fizyki UwB, dr Ewa Młyńczak z Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Kraków wygłosi wykład pt:

Fundamental electronic properties of epitaxial Fe(001) films grown on Au(001).

Serdecznie zapraszamy

Andrzej Maziewski

Jerzy Przeszowski

Fundamental electronic properties of epitaxial Fe(001) films grown on Au(001).

Dr Ewa Młyńczak
Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Kraków

Fe is a prototypical itinerant ferromagnet that have been studied extensively in the context of magnetism and spintronics. During this presentation, I will demonstrate that the thin films of Fe(001) of exceptional crystalline quality can be grown on Au(001) single crystal substrates using molecular beam epitaxy at liquid nitrogen temperature. I will present the results of the electronic band structure studies of such films performed using high-resolution lab-based angle-resolved photoemission spectroscopy (ARPES) as well as synchrotron-based k-space microscopy (NanoESCA). The combination of high-quality epitaxial thin films with state-of-the-art measurement techniques enabled unraveling for the first time such phenomena as: i) magnetization-depended switching of the spin-orbit gaps near the Fermi level [1], ii) existence of the high-energy (Eb=1.5 eV) dispersion anomaly that results from the electron-magnon interaction [2] and iii) occurrence of the magnetization-dependent quantum-well states [3]. The experimental results will be compared with the ab-initio calculations of the electronic band structure of Fe performed within the density functional theory (local density approximation and generalized gradient approximation) as well as using the GW method [4]. The experimental spectra will be compared not only to the theoretical initial electronic states but also to the simulations of photoemission performed taking into account the finite thickness of the films and broadening of the wavevector perpendicular to the sample surface. I will also discuss implications of these results for the magnetotransport effects such as an intrinsic anomalous Hall effect.
[1]. E. Młyńczak et al., Phys. Rev. X 6, 041048 (2016)
[2]. E. Młyńczak et al., Nature Comm. 10, 505 (2019)
[3]. E. Młyńczak et al., Phys. Rev. B. 103‚ 035134 (2021)
[4]. E. Młyńczak et al., Phys. Rev. B, 105, 115135 (2022)