Properties of high-$T_c$ copper oxides from band models of spin-phonon coupling

TL;DR

This paper investigates the role of spin-phonon coupling in high-temperature copper oxides using band models, explaining various observed properties and phenomena such as the pseudogap and spin excitations.

Contribution

It introduces a band model based on ab-initio calculations and NFE approximation to explain the effects of spin-phonon coupling in high-$T_c$ copper oxides, highlighting its influence on pseudogap formation and spin dynamics.

Findings

The pseudogap is caused by spin-phonon coupling along [1,0,0].

Secondary waves along [1,1,0] contribute to the 'waterfall' structure.

Conditions for optimal $T_C$ and surface spin enhancement are discussed.

Abstract

The mechanism of spin-phonon coupling (SPC) and possible consequencies for the properties of high-$T_C$ copper oxides are presented. The results are based on ab-initio LMTO band calculations and a nearly free-electron (NFE) model of the band near $E_F$. Many observed properties are compatible with SPC, as for the relation between doping and $\vec{q}$ for spin excitations and their energy dependence. The main pseudogap is caused by SPC and waves along [1,0,0], but it is suggested that secondary waves, generated along [1,1,0], contribute to a 'waterfall' structure. Conditions for optimal $T_C$, and the possiblities for spin enhancement at the surface are discussed.