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arXiv · 0909.2077

Spin-charge decoupling and the photoemission line-shape in one dimensional insulators

Valeria Lante·Alberto Parola
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Abstract

The recent advances in angle resolved photoemission techniques allowed the unambiguous experimental confirmation of spin charge decoupling in quasi one dimensional (1D) Mott insulators. This opportunity stimulates a quantitative analysis of the spectral function $A(k,\omega)$ of prototypical one dimensional correlated models. Here we combine Bethe Ansatz results, Lanczos diagonalizations and field theoretical approaches to obtain $A(k,\omega)$ for the 1D Hubbard model as a function of the interaction strength. By introducing a {\it single spinon approximation}, an analytic expression is obtained, which shows the location of the singularities and allows, when supplemented by numerical calculations, to obtain an accurate estimate of the spectral weight distribution in the $(k,\omega)$ plane. Several experimental puzzles on the observed intensities and line-shapes in quasi 1D compounds, like ${\rm SrCuO_2}$, find a natural explanation in this theoretical framework.

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Valeria Lante, Alberto Parola. 2009-09-11. Spin-charge decoupling and the photoemission line-shape in one dimensional insulators. https://doi.org/10.1103/physrevb.80.195113

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