Large electron-phonon interactions from FeSe phonons in a monolayer

Sinisa Coh; Marvin L. Cohen; Steven G. Louie

doi:10.1088/1367-2630/17/7/073027

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arXiv · 1407.5657

Large electron-phonon interactions from FeSe phonons in a monolayer

Sinisa Coh·Marvin L. Cohen·Steven G. Louie

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Abstract

We show that electron-phonon coupling can induce strong electron pairing in an FeSe monolayer on a SrTiO3 substrate (experimental indications for superconducting Tc are between 65 and 109K). The role of the SrTiO3 substrate in increasing the coupling is two-fold. First, the interaction of the FeSe and TiO2 terminated face of SrTiO3 prevents the FeSe monolayer from undergoing a shear-type (orthorhombic, nematic) structural phase transition. Second, the substrate allows an anti-ferromagnetic ground state of FeSe which opens electron-phonon coupling channels within the monolayer that are prevented by symmetry in the non-magnetic phase. The spectral function for the electron-phonon coupling (alpha2F) in our calculations agrees well with inelastic tunneling data.

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Sinisa Coh, Marvin L. Cohen, Steven G. Louie. 2014-07-21. Large electron-phonon interactions from FeSe phonons in a monolayer. https://doi.org/10.1088/1367-2630/17/7/073027

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