Optics clues to pairing glues in high T$_{c}$ cuprates

TL;DR

This paper analyzes optical spectra of high T_c cuprates using minimal electron-boson coupling models, finding both marginal Fermi liquid and spin fluctuation theories can fit data with an added scattering channel at 55 meV.

Contribution

It demonstrates that both marginal Fermi liquid and spin fluctuation models can describe optical spectra when including an extra scattering channel at 55 meV.

Findings

Both theories fit experimental data with an additional 55 meV scattering channel.

Histogram representation of bosonic spectral density provides new insights.

Optical spectra analysis constrains electron-boson interaction models.

Abstract

We analyze optical spectra of high temperature superconductors using a minimal model of electrons coupled to bosons. We consider the marginal Fermi liquid theory and the spin fluctuation theory, as well as a histogram representation of the bosonic spectral density. We find that the two theories can both be used to describe the experimental data provided that we allow for an additional scattering channel with an energy of 55 meV.