Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface

doi:https://doi.org/10.1063/1.4876750

Title: Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface

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Abstract

The electronic structure, phonon dispersions, and electron-phonon (EP) coupling in Fe{sub 2}Se{sub 2}/SrTiO{sub 3} (FeSe/STO) thinnest films are studied based on the first-principles calculations. It is found that the FeSe/STO interface with lattice strain leads to a change of band structures and a significant enhancement of the EP coupling, the latter being close related to interface-induced ferroelectric phonons coupled to electrons on the FeSe monolayer. In the FeSe/STO system, T{sub c} of phonon-induced superconductivity is estimated to be much greater than that in the bulk FeSe, but still well below the experimental value of an FeSe monolayer on the STO substrate, indicating that the electron-phonon mechanism alone cannot explain its high T{sub c}.

Authors:

Li, B. ^[1]; Huang, G. Q. ^[2]

National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093 (China)
Departement of Physics, Nanjing Normal University, Nanjing 210023 (China)

Publication Date:: 2014-05-21

OSTI Identifier:: 22304416

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 115; Journal Issue: 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DISPERSIONS; ELECTRONIC STRUCTURE; ELECTRON-PHONON COUPLING; FERROELECTRIC MATERIALS; FILMS; INTERFACES; IRON SELENIDES; PHONONS; STRAINS; STRONTIUM TITANATES; SUBSTRATES; SUPERCONDUCTIVITY; TRANSITION TEMPERATURE

Citation Formats


                    Li, B., College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, Xing, Z. W., E-mail: zwxing@nju.edu.cn, Huang, G. Q., National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, and Xing, D. Y., E-mail: dyxing@nju.edu.cn. Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4876750.

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                    Li, B., College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, Xing, Z. W., E-mail: zwxing@nju.edu.cn, Huang, G. Q., National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, & Xing, D. Y., E-mail: dyxing@nju.edu.cn. Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface.  United States.  https://doi.org/10.1063/1.4876750

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                    Li, B., College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, Xing, Z. W., E-mail: zwxing@nju.edu.cn, Huang, G. Q., National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, and Xing, D. Y., E-mail: dyxing@nju.edu.cn. Wed .  
        "Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface".  United States.  https://doi.org/10.1063/1.4876750.

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@article{osti_22304416,

  title        = {Electron-phonon coupling enhanced by the FeSe/SrTiO{sub 3} interface},

  author       = {Li, B. and College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023 and Xing, Z. W., E-mail: zwxing@nju.edu.cn and Huang, G. Q. and National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093 and Xing, D. Y., E-mail: dyxing@nju.edu.cn},

  abstractNote = {The electronic structure, phonon dispersions, and electron-phonon (EP) coupling in Fe{sub 2}Se{sub 2}/SrTiO{sub 3} (FeSe/STO) thinnest films are studied based on the first-principles calculations. It is found that the FeSe/STO interface with lattice strain leads to a change of band structures and a significant enhancement of the EP coupling, the latter being close related to interface-induced ferroelectric phonons coupled to electrons on the FeSe monolayer. In the FeSe/STO system, T{sub c} of phonon-induced superconductivity is estimated to be much greater than that in the bulk FeSe, but still well below the experimental value of an FeSe monolayer on the STO substrate, indicating that the electron-phonon mechanism alone cannot explain its high T{sub c}.},

  doi          = {10.1063/1.4876750},

  url          = {https://www.osti.gov/biblio/22304416},
  journal      = {Journal of Applied Physics},

  issn         = {0021-8979},

  number       = 19,

  volume       = 115,

  place        = {United States},

  year         = {2014},

  month        = {5}

}

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