Why does $\mathrm{SrTiO_3}$ raise the transition temperature of monolayer FeSe?
In plain words
Electrons donated by the substrate explain part of the rise, since FeSe doped with electrons in other ways reaches about 40 to 48 K. Whether vibrations of the substrate supply the rest is disputed.
Precise statement
Monolayer FeSe/$\mathrm{SrTiO_3}$(001) has only electron pockets at M (about 0.1 e per Fe), with a gap of $\sim 15-20\,\mathrm{meV}$ that closes near $55-65\,\mathrm{K}$ in photoemission, while electron-doped FeSe without $\mathrm{SrTiO_3}$ (K dosing, ionic gating) reaches $\sim 40-48\,\mathrm{K}$. Determine the separate contributions to $T_c$ of electron doping, interfacial electron-phonon coupling to $\mathrm{SrTiO_3}$ polar (Fuchs-Kliewer) phonons at $\sim 80-100\,\mathrm{meV}$ through small-momentum forward scattering, and substrate screening.
What would settle it
$T_{c}$ of monolayer FeSe at fixed doping on substrates with systematically varied polar-phonon coupling, compared with a quantitative pairing calculation.
Status in the literature
Unverified note: it names recent work and was partly written without a live literature search; it awaits a check by an editor.
Inserting a metallic $\mathrm{SrVO_3}$ layer that screens interfacial phonons lowered the pairing temperature to about 48 K (Guo et al., Nano Letters, 2024, arXiv 2407.09880), supporting a role for interfacial electron-phonon coupling.
Problems built on this one
Special cases
Results
No results have been posted on this problem yet.
Post a result · how results are checked
Sign in to follow or save this problem
See also
- Related Why does $\mathrm{KTaO_3}$ interface superconductivity depend on crystal orientation?
- Related What is the zero-resistance transition temperature of monolayer FeSe on $\mathrm{SrTiO_3}$?
- Related Pairing symmetry of heavily electron-doped FeSe without hole pockets
- Related Pairing symmetry of monolayer FeSe on $\mathrm{SrTiO_3}$
Comments (0)
Comments are not records: they are not signed, stamped or logged. How comments work
No comments yet.
Sign in to comment.