We have investigated the low-energy electronic structure of the strongly correlated one-dimensional copper oxide chain compound SrCuO2 by angle resolved photoemission as a function of excitation energy. In addition to the prominent spinon-holon continuum we observe a peaklike and dispersive feature at the zone boundary. By fine-tuning the experimental parameters we are able to monitor the full holon branch and to directly measure the electronic hopping parameter with unprecedented accuracy.
@article{arxiv.cond-mat/0606238,
title = {Current spinon-holon description of the one-dimensional charge-transfer insulator SrCuO2: Angle-resolved photoemission measurements},
author = {A. Koitzsch and S. V. Borisenko and J. Geck and V. B. Zabolotnyy and M. Knupfer and J. Fink and P. Ribeiro and B. Buechner and R. Follath},
journal= {arXiv preprint arXiv:cond-mat/0606238},
year = {2009}
}