Renormalization of electrons in bilayer cuprate superconductors

Renormalization of dispersion in electron-doped bilayer cuprate superconductors

“…In this case, a bewildering variety of electronic orders described by the quasiparticle scattering processes with the scattering wave vectors q i therefore is driven by this EFS instability [40][41][42][43] . These intrinsic features of the EFS reconstruction resemble these obtained for the corresponding hole-doped case 29 . We are now ready to discuss the bilayer coupling effect on the quasiparticle dispersion kink in the electron-doped bilayer cuprate superconductors.…”

“…It is commonly accepted that the essential physics of the doped CuO 2 layer can be described by the t-J model on a square lattice 28 . However, for the discussions of the bilayer coupling effect on the quasiparticle dispersion kink in the electron-doped bilayer cuprate superconductors, the single-layer t-J model can be extended by the consideration of the bilayer coupling as 29 ,…”

“…which therefore leads to that the bilayer magnetic exchange J ⊥ = (t ⊥ /t) 2 J. This bilayer t-J model ( 1) is supplemented by the local constraint σ C † laσ C laσ ≥ 1 to remove zero electron occupancy, which is different from the hole-doped case 29 , where the local constraint is subjected to remove double electron occupancy, and can be treated properly in terms of the charge-spin separation fermionspin transformation 35,36 . However, for the application of this fermion-spin transformation to treat the local constraint in the electron-doped side, we can work in the hole representation via a particle-hole transformation C laσ → f † la−σ .…”

“…Within the bilayer t-J model in the fermion-spin representation, the renormalization of the dispersion in the hole-doped bilayer cuprate superconductors 29 has been investigated based on the kinetic-energy-driven superconductivity [36][37][38][39] , where the kink effect in the quasiparticle dispersion is enhanced by the strong bilayer coupling. Following these previous discussions 29 , the hole normal and anomalous Green's functions of the bilayer t-J model (3) in the bonding-antibonding representation can be obtained explicitly as,…”

“…In cuprate superconductors, the topology of EFS plays an essential role in the understanding of the unconventional properties, since everything happens at around EFS. In particular, the strong coupling between the electrons and a strongly dispersive spin excitation in cuprate superconductors leads to a strong redistribution of the spectral weights on EFS 27,29 , and then a bewildering variety of electronically ordered states is driven by this q 1 q 2 q 3 q 4 q 5 q 6 q 7 0.0 -0.5 -1.0 0.5 1.0…”