Polaronic effect and its impact on Tc for novel layered superconducting systems

TL;DR

This paper explores how the polaronic effect, arising from ions with double-well potentials in complex layered superconductors, enhances electron-lattice interactions and potentially increases the critical temperature (Tc).

Contribution

It introduces a model linking ion double-well structures to increased electron-lattice coupling and superconducting Tc in layered systems.

Findings

Polaronic effects significantly strengthen electron pairing.

Double-well ion subsystems enhance electron-lattice interactions.

Potential increase in Tc due to lattice effects.

Abstract

The crystal lattice of a complex compound may contain a subsystem of ions with each one possessing two close equilibrium positions (double-well structure). For example, the oxygen ions in the cuprates form such a subsystem. In such a situation it is impossible to separate electronic and local vibrational motions. This leads to a large increase in the effective strength of the electron-lattice interaction, which is beneficial for pairing.