Aller au contenu directement

Multiband charge density wave exposed in a transition metal dichalcogenide

Published on October 18, 2021

In the presence of multiple bands, well-known electronic instabilities may acquire new complexity. While multiband superconductivity is the subject of extensive studies, the possibility of multiband charge density waves (CDWs) has been largely ignored so far. Here, combining energy dependent scanning tunnelling microscopy (STM) topography with a simple model of the charge modulations and a self-consistent calculation of the CDW gap, we find evidence for a multiband CDW in 2H-NbSe2. This CDW not only involves the opening of a gap on the inner band around the K-point, but also on the outer band. This leads to spatially out-of-phase charge modulations from electrons on these two bands, which we detect through a characteristic energy dependence of the CDW contrast in STM images.

Collaboration with Jasper van Wezel, Amsterdam, and Felix Flicker, Cardiff.

See the News and Views published in Nature Physics.

Authors

Árpád Pásztor, Alessandro Scarfato, Marcello Spera, Felix Flicker, Céline Barreteau, Enrico Giannini, Jasper van Wezel and Christoph Renner

See this publication on UNIGE