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arXiv · 0707.2267

High energy kink in the dispersion of a hole in an antiferromagnet -- double-occupancy effects on electronic excitations

Pooja Srivastava·Saptarshi Ghosh·Avinash Singh
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Abstract

Evolution of the hole spectral function along the Gamma-(pi,pi) cut is studied in the antiferromagnetic state of the Hubbard model. The kink in the calculated hole dispersion, the sharp spectral-weight transfer between the branches, and the drastically suppressed coherent spectral weight near k=(0,0), as observed recently in the high-resolution ARPES studies of cuprate antiferromagnets, are shown to be strongly enhanced by finite-U double-occupancy effects. Together with the anomalous spin-wave dispersion observed earlier in high-resolution neutron-scattering studies, the present study provides further evidence of a unified description of magnetic and electronic excitations in cuprate antiferromagnets in terms of the Hubbard model.

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Pooja Srivastava, Saptarshi Ghosh, Avinash Singh. 2007-07-16. High energy kink in the dispersion of a hole in an antiferromagnet -- double-occupancy effects on electronic excitations. https://doi.org/10.1103/physrevb.76.184435

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