Visualizing electron pockets in cuprate superconductors

TL;DR

This paper introduces a theoretical framework to detect electron pockets in cuprate superconductors using spectroscopic methods, addressing a long-standing mystery by linking experimental signatures across STM, INS, and ARPES.

Contribution

The authors develop a novel theoretical approach to identify electron pockets in cuprates through multiple spectroscopic techniques, providing new interpretative tools for experimental data.

Findings

QPI patterns reveal additional scattering vectors due to electron pockets.

A second magnetic resonance mode may appear in INS spectra.

Reanalysis of experimental data shows direct fingerprints of electron pockets.

Abstract

Fingerprint of the electron-pocket in cuprates has been obtained only in numerous magneto-transport measurements, but its absence in spectroscopic observations pose a long-standing mystery. We develop a theoretical tool to provide ways to detect electron-pockets via numerous spectroscopies including scanning tunneling microscopy (STM) spectra, inelastic neutron scattering (INS), and angle-resolved photoemission spectroscopy (ARPES). We show that the quasiparticle-interference (QPI) pattern, measured by STM, shows additional 7 ${\bm q}$ vectors associated with the scattering on the electron-pocket, than that on the hole-pocket. Furthermore, the Bogolyubov quasiparticle scatterings of the electron pocket may lead to a second magnetic resonance mode in the INS spectra at a higher resonance energy. Finally, we reanalyze some STM, INS, and ARPES experimental data of several cuprate compounds which dictates the direct fingerprints of electron pockets in these systems.