Antiferromagnetically Induced Photoemission Band in the Cuprates

Strong antiferromagnetic correlations in models of high critical temperature (high- T_c) cuprates produce quasiparticlelike features in photoemission (PES) calculations above the Fermi momentum p_F corresponding to weakly interacting electrons. This effect, discussed before by Kampf and Schrieffer [Phys. Rev. B 41, 6399 (1990)], is analyzed here using computational techniques in strong coupling. It is concluded that weight above p_F should be observable in PES data for underdoped compounds, while in the overdoped regime it will be hidden in the experimental background. At optimal doping the signal is weak. The order of magnitude of our results is compatible with experimental data by Aebi et al. [Phys. Rev. Lett. 72, 2757 (1994)] for Bi₂Sr₂CaCu₂O₈.