Band structure and charge doping effects of potassium-adsorbed FeSe/SrTiO3 system

Abstract

We theoretically study, through combining the density functional theory and an unfolding technique, the electronic band structure and the charge doping effects for the deposition of potassium (K) on multilayer FeSe films grown on SrTiO3 (001) surface. These results form a theoretical base line for further detailed studies of low-temperature electronic properties and their multiway quantum engineering of FeSe thin films. We explain the Fermi surface topology observed in experiment and formulate the amount of doped electrons as a function of atomic K coverage. We show that the atomic K deposition efficiently dopes electrons to top layer FeSe. Both checkerboard and pair-checkerboard antiferromagnetic (AFM) FeSe layers show electron pockets at M point and no Fermi pocket at $\Gamma$ point with moderate atomic K coverage. The electron transfer from K adsorbate to FeSe film introduces a strong electric field, which leads to a double-Weyl cone structure at M point in the Brillouin zone of checkerboard-AFM FeSe. We demonstrate that with experimentally accessible heavy electron doping, an electron-like Fermi pocket will emerge at $\Gamma$ point, which should manifest itself in modulating the high-temperature superconductivity of FeSe thin films.

14 pages, 5 figures, unfolded band structure for pair-checkerboard antiferromagnetic phase is added in the revised manuscript

References in corpus (19)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Superconductivity in single-layer films of FeSe with a transition temperature above 100 K
• Common Electronic Origin of Superconductivity in (Li,Fe)OHFeSe Bulk Superconductor and Single-Layer FeSe/SrTiO3 Films
• Observation of universal strong orbital-dependent correlation effects in iron chalcogenides
• Plain s-wave superconductivity in single-layer FeSe on SrTiO3 probed by scanning tunneling microscopy
• Enhanced superconductivity due to forward scattering in FeSe thin films on SrTiO3 substrates
• Onset of the Meissner effect at 65 K in FeSe thin film grown on Nb doped SrTiO3 substrate
• Atomic and electronic structures of FeSe monolayer and bilayer thin films on SrTiO${}_3$ (001): a first-principles study
• Topological Phases in the Single-Layer FeSe
• Antiferromagnetic ground state with pair-checkboard order in FeSe
• Revealing the Empty-State Electronic Structure of Single-Unit-Cell FeSe/SrTiO${}_3$
• Effects of charge doping and constrained magnetization on the electronic structure of an FeSe monolayer
• Superconductivity dichotomy in K-coated single and double unit cell FeSe films on SrTiO3
• Oxygen Vacancy Induced Flat Phonon Mode at FeSe /SrTiO3 interface
• Thickness dependence of superconductivity and superconductor-insulator transition in ultrathin FeSe films on SrTiO3(001) substrate
• A general group theoretical method to unfold band structures and its application
• Thickness-Dependent Coherent Phonon Frequency in Ultrathin FeSe/SrTiO${}_3$ Films
• Quantum Unfolding: A program for unfolding electronic energy bands of materials
• First-principles study of magnetic frustration in FeSe epitaxial films on SrTiO${}_3$

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• Magnetic fluctuations and spin-spirals in single-layer FeSe
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• Effects of interface oxygen vacancies on electronic bands of FeSe/SrTiO3(001)
• MagGene: A genetic evolution program for magnetic structure prediction
• Role of electric fields on enhanced electron correlation in surface-doped FeSe
• Gigantic work function in layered AgF2
• Stealth Majorana Zero Mode in a Trilayer Heterostructure MnTe/Bi2Te3/Fe(Te,Se)
• Enhanced Surface Superconductivity in Ba(Fe${}_{0.95}$Co${}_{0.05}$)${}_2$As${}_2$