UNIGE document Scientific Article
previous document  unige:23851  next document
add to browser collection
Title

First direct observation of the Van Hove singularity in the tunnelling spectra of cuprates

Authors
Published in Nature Communications. 2011, vol. 2, p. 221
Abstract In two-dimensional (2D) lattices, the electronic levels are unevenly spaced, and the density of states (DOS) displays a logarithmic divergence known as the Van Hove singularity (VHS). This is the case in particular for the layered cuprate superconductors. The scanning tunnelling microscope (STM) probes the DOS, and is therefore the ideal tool to observe the VHS. No STM study of cuprate superconductors has reported such an observation so far giving rise to a debate about the possibility of observing directly the normal state DOS in the tunnelling spectra. In this study, we show for the first time that the VHS is unambiguously observed in STM measurements performed on the cuprate Bi2Sr2CuO6+δ (Bi-2201). Beside closing the debate, our analysis proves the presence of the pseudogap in the overdoped side of the phase diagram of Bi-2201 and discredits the scenario of the pseudogap phase crossing the superconducting dome.
Identifiers
Full text
Structures
Citation
(ISO format)
PIRIOU, Alexandre et al. First direct observation of the Van Hove singularity in the tunnelling spectra of cuprates. In: Nature Communications, 2011, vol. 2, p. 221. https://archive-ouverte.unige.ch/unige:23851

183 hits

143 downloads

Update

Deposited on : 2012-11-07

Export document
Format :
Citation style :