Fig. 3: The calculated phonon DOS, dispersion, and electron–phonon coupling at FeSe/SrTiO3 interface.
From: Atomic-scale observation of localized phonons at FeSe/SrTiO3 interface
a The calculated phonon density of states (PDOS) extracted from bulk SrTiO3 (blue), Ti–O(B) in the interface structure(purple), Ti–O(T) in the interface structure (orange), FeSe layer in the interface structure (yellow) and bulk FeSe (green). The red and black arrows point to the main features that are enhanced at Ti–O(T) and Ti–O(B) layers, respectively. b Phonon linewidths due to electron–phonon coupling mapped on phonon dispersion and the Eliashberg spectral function at Γ point for calculated structure. The phonon with energy ~83 meV has the strongest coupling strength with FeSe electrons at Γ point, i.e., strongly coupling interfacial (SCI) mode. c The side view (upper panel) and top view (lower panel) of phonon eigenvectors of SCI mode in calculated interface structure.
