Unconventional exciton evolution from the pseudogap to superconducting phases in cuprates

Abstract

The nature of the excitations in the pseudogap regime and their relation to superconductivity remain core issues in cuprate high-T c superconductivity. Here, using resonant inelastic x-ray scattering, the authors find that high-energy excitons in optimally-doped Bi2Sr2CaCu2O8+δ are enhanced by the onset of superconductivity, an effect possibly explained in terms of electron fractionalization.