Orbital- and kz-selective hybridization of Se 4p and Ti 3d states in the charge density wave phase of TiSe2

DOI: 10.1103/PhysRevLett.122.076404

Authors: Matthew D. Watson (University of St. Andrews; Diamond Light Source) , Oliver J. Clark (University of St. Andrews) , Federico Mazzola (University of St. Andrews) , Igor Marković (University of St. Andrews; Max Planck Institute for Chemical Physics of Solids) , Veronika Sunko (University of St. Andrews; Max Planck Institute for Chemical Physics of Solids) , Timur K. Kim (Diamond Light Source) , Kai Rossnagel (Christian-Albrechts-Universität zu Kiel; Deutsches Elektronen-Synchrotron DESY) , Philip King (University of St. Andrews)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review Letters , VOL 122

State: Published (Approved)
Published: February 2019
Diamond Proposal Number(s): 19771 , 18555 , 16262

Abstract: We revisit the enduring problem of the 2 × 2 × 2 charge density wave (CDW) order in TiSe2, utilizing photon energy-dependent angle-resolved photoemission spectroscopy to probe the full three-dimensional high- and low-temperature electronic structure. Our measurements demonstrate how a mismatch of dimensionality between the 3D conduction bands and the quasi-2D valence bands in this system leads to a hybridization that is strongly kz dependent. While such a momentum-selective coupling can provide the energy gain required to form the CDW, we show how additional “passenger” states remain, which couple only weakly to the CDW and thus dominate the low-energy physics in the ordered phase of TiSe2.

Journal Keywords: Charge density waves; Electronic structure; Transition-metal dichalcogenide; Angle-resolved photoemission spectroscopy

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Added On: 13/03/2019 09:50

Discipline Tags:

Physics Hard condensed matter - structures Materials Science Metallurgy

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)