Doublon-like excitations and their phononic coupling in a Mott charge-density-wave system

Abstract

Electron-phonon-driven charge density waves can in some circumstances allow electronic correlations to become predominant, driving a system into a Mott insulating state. New insights into both the Mott state and preceding charge density wave may result from observations of the coupled dynamics of their underlying degrees of freedom. Here, tunneling injection of single electrons into the upper Hubbard band of the Mott charge-density-wave material 1T-TaS2 reveals extraordinarily narrow electronic excitations which couple to amplitude mode phonons associated with the charge density wave's periodic lattice distortion. This gives a vivid microscopic view of the interplay between excitations of the Mott state and the lattice dynamics of its charge density wave precursor.

8 pages, 5 figures, with Supplementary Information (6 pages, 8 figures). Accepted for publication in Physical Review X

References in corpus (6)

• Fermi surface nesting and the origin of Charge Density Waves in metals
• Band insulator to Mott insulator transition in 1T-TaS${}_2$
• Possible strain induced Mott gap collapse in 1T-TaS${}_2$
• Multiple crossovers and coherent states in a Mott-Peierls insulator
• Surface structure and stacking of the commensurate $\left(\sqrt{13}\times \sqrt{13}\right)$R13.9° charge density wave phase of 1T-TaS${}_2$(0001)
• Signatures of coherent electronic quasiparticles in the paramagnetic Mott insulator