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Doping dependent quasiparticle band structure in cuprate superconductors

R. Eder·Y. Ohta·G. A. Sawatzky
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Abstract

We present an exact diagonalization study of the single particle spectral function in the so-called t-t'-t''-J model in 2D. As a key result, we find that unlike the `pure' t-J model, hole doping leads to a major reconstruction of the quasiparticle band structure near (pi,0): whereas for the undoped system the quasiparticle states near (pi,0) are deep below the top of the band at (pi/2,pi/2), hole doping shifts these states up to E_F, resulting in extended flat band regions close to E_F and around (pi,0). This strong doping-induced deformation can be directly compared to angle resolved photoemission results on Sr_2 Cu Cl_2 O_2, underdoped Bi2212 and optimally doped Bi2212. We propose the interplay of long range hopping and decreasing spin correlations as the mechanism of this deformation.

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R. Eder, Y. Ohta, G. A. Sawatzky. 1996-11-05. Doping dependent quasiparticle band structure in cuprate superconductors. https://doi.org/10.1103/physrevb.55.r3414

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