Effect of the nonmonotonic d-wave superconducting gap on the electronic Raman scattering of electron-doped cuprate superconductors

摘要

By considering a nonmonotonic d-wave superconducting (SC) gap effect in electron-doped cuprate superconductors, the energy and momentum dependence of the electronic Raman scattering is studied. The electronic Raman scattering of electron-doped cuprate superconductors has obvious differences with hole-doped case described by a pure d-wave SC gap, which can be attributed to the nonmonotonic d-wave SC gap in electron-doped cuprate superconductors. Three main different behaviours for the electronic Raman scattering spectra between electrondoped and hole-doped cuprate superconductors have been obtained, the intensity comparison of B_(1g) and B_(2g) spectra, the Raman peak positions as a function of energy for B_(1g) and B_(2g) spectra, and energy asymptotic behaviour of the low-energy B_(1g) spectrum. For electron-doped cuprate superconductors, the intensity of B_(2g) spectrum as a function of energy is larger than B_(1g) one, and the Raman peak position of B_(2g) spectrum appears at a higher energy than B_(1g) one, then the low-energy spectrum of B_(1g) as a function of energy increases linearly, not v3 energy dependence. All these theoretical results of electron-doped cuprate superconductors are in qualitative agreement with the corresponding Raman scattering experimental data.