TY  - JOUR
AU  - Mlynczak, Ewa
AU  - Aguilera, Irene
AU  - Gospodaric, Pika
AU  - Heider, T.
AU  - Jugovac, M.
AU  - Zamborlini, G.
AU  - Tusche, C.
AU  - Suga, Shigemasa
AU  - Feyer, V.
AU  - Blügel, S.
AU  - Plucinski, L.
AU  - Schneider, C. M.
TI  - Spin-polarized quantized electronic structure of Fe(001) with symmetry breaking due to the magnetization direction
JO  - Physical review / B
VL  - 103
IS  - 3
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2021-00543
SP  - 035134
PY  - 2021
AB  - Quantum well states formed by d electrons in metallic thin films are responsible for many fundamental phenomena that oscillate with layer thickness, such as magnetic anisotropy or magnetoresistance. Using momentum microscopy and angle-resolved photoemission, we mapped in unprecedented detail the quantized electronic states of Fe(001) in a broad photon energy range starting from soft x-ray (160 eV) down to vacuum ultraviolet (8.4 eV). We show that it is possible to simulate the experimentally observed photoemission spectra with high accuracy by using the ab initio electronic bulk band structure as the initial state, taking into account that free electron final electronic states are intrinsically broadened along the wave vector direction perpendicular to the sample surface. To simulate the thin-film case, we take into account a subset of the initial electronic states, which results in the reproduction of the quantized electronic structure observed in the experiment. In addition, we present results of the spin-sensitive measurements, which are confronted with the photoemission simulation that takes into account the spin degree of freedom. We demonstrate electronic states that can be responsible for the oscillations of the magnetic anisotropy in Fe(001) thin films with periods of about 5 and 9 monolayers. We show that these quantum well states change position in reciprocal space depending on the magnetization direction. Our photoemission simulation reproduces this effect, which highlights its origin in the relativistic bulk electronic band structure of bcc Fe. We also observed magnetization-dependent spin-orbit gaps with the symmetry lower than the bulk symmetry. We believe that the same method of simulating photoemission spectra might facilitate interpretation of the photoemission intensities measured for other three-dimensional materials, especially when the spin-polarized quantized electronic states are considered.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000609013000002
DO  - DOI:10.1103/PhysRevB.103.035134
UR  - https://juser.fz-juelich.de/record/889937
ER  -