We present a soft x-ray angle-resolved photoemission spectroscopy study of the overdoped high-temperature superconductors La2−xSrxCuO4 and La1.8−xEu0.2SrxCuO4. In-plane and out-of-plane components of the Fermi surface are mapped by varying the photoemission angle and the incident photon energy. No kz dispersion is observed along the nodal direction, whereas a significant antinodal kz dispersion is identified. Based on a tight-binding parametrization, we discuss the implications for the density of states near the van-Hove singularity. Our results suggest that the large electronic specific heat found in overdoped La2−xSrxCuO4 can not be assigned to the van-Hove singularity alone. We therefore propose quantum criticality induced by a collapsing pseudogap phase as a plausible explanation for observed enhancement of electronic specific heat.
@article{arxiv.1804.08019,
title = {Three-Dimensional Fermi Surface of Overdoped La-Based Cuprates},
author = {M. Horio and K. Hauser and Y. Sassa and Z. Mingazheva and D. Sutter and K. Kramer and A. Cook and E. Nocerino and O. K. Forslund and O. Tjernberg and M. Kobayashi and A. Chikina and N. B. M. Schröter and J. A. Krieger and T. Schmitt and V. N. Strocov and S. Pyon and T. Takayama and H. Takagi and O. J. Lipscombe and S. M. Hayden and M. Ishikado and H. Eisaki and T. Neupert and M. Månsson and C. E. Matt and J. Chang},
journal= {arXiv preprint arXiv:1804.08019},
year = {2018}
}