Theoretical Investigation of the Four-Layered Self-Doped High-TcSuperconductors: Evidence of the Pair Tunneling Effect

Abstract

Based on a four-layered self-doped t-J type model and the slave-boson mean-field approach, we study theoretically the superconductivity in the electron-doped and hole-doped layers. The neighbor layers are coupled through both the single electron interlayer hopping and pair tunneling effect. The superconducting gap magnitude for the electron-doped band is nearly twice that of the hole-doped one, which contrasts with our previous understanding of the electron-hole asymmetry in high-T(c) superconductors but is consistent with recent angle-resolved photoemission spectroscopy experiments in four-layered materials Ba2Ca3Cu4O8F2. Our results propose that the pair tunneling effect is important to examine the multilayered superconducting materials.