Plasmon assisted superconductivity in LiTi$_2$O$_4$

TL;DR

This study uses advanced theoretical methods to show that plasmons significantly contribute to the high superconducting transition temperature in LiTi₂O₄, aligning well with experimental data.

Contribution

It introduces a combined theoretical framework to demonstrate the role of plasmons in superconductivity of LiTi₂O₄, highlighting the importance of dynamical Coulomb interactions.

Findings

Excellent agreement with experimental data for key properties.

Plasmons play a crucial role in pairing mechanism.

Dynamical Coulomb interactions are essential for accurate modeling.

Abstract

We combine $GW$ plus extended dynamical mean field theory ($GW$+EDMFT) with the density functional theory for superconductors (SCDFT) framework to study the electronic properties of LiTi$_2$O$_4$. Excellent agreement with experiment is obtained for the density of states, mass enhancement, Sommerfeld coefficient and superconducting $T_c$, if the dynamical nature of the screened Coulomb interaction is taken into account. Our results show that the coupling to collective charge fluctuations (plasmons) plays an important role in the pairing mechanism and explains the remarkably high $T_c$ of this moderately correlated spinel compound.