Three-Dimensional Fermi-Surface and Electron-Phonon Coupling in Semimetallic 1T-TiTe2 studied by Angle-Resolved Photoemission Spectroscopy

TL;DR

This study uses high-resolution ARPES to reveal the three-dimensional electronic structure, Fermi surface complexity, and electron-phonon interactions in semimetallic 1T-TiTe2, providing insights into its electronic properties.

Contribution

First experimental observation of a kink in 1T-TiTe2 indicating electron-phonon coupling and detailed mapping of its 3D electronic structure.

Findings

Pronounced 3D electronic structure of 1T-TiTe2.

Multiple Fermi surface sheets and complex band structure.

Observation of a kink at 18 meV below the Fermi energy.

Abstract

We present an investigation on electronic structure of 1T-TiTe2 material via high-resolution angle-resolved photoemission spectroscopy (ARPES), utilizing tunable photon energy excitations. The typical semimetal-like electronic structure is observed and examined, where multiple hole pockets related to Te 5p bands and one electron pockets related to Ti 3d band are populated. The obtained results reveals i) a pronounced three-dimensional (3D) electronic structure of 1T-TiTe2 with typical semi-metallic features, for both the Ti 3d and the Te 5p states; ii) multiple Fermi surface (FS) sheets and complex band structure; and iii) an obvious kink in dispersion at an energy of about 18 meV below the Fermi energy, the first experimental observation of a kink structure in 1T-TiTe2, which may originate from electron-phonon coupling. These important and significant findings can help us to gain an in-depth understanding of the 3D electronic structure of semimetallic 1T- TiTe2.