Terahertz spectroscopy of collective charge density wave dynamics at the atomic scale.

ABSTRACT: Charge density waves are wave-like modulations of a material's electron density that display collective amplitude and phase dynamics. The interaction with atomic impurities induces strong spatial heterogeneity of the charge-ordered phase. Direct real-space observation of phase excitation dynamics of such defect-induced charge modulation is absent. Here, by utilizing terahertz pump-probe spectroscopy in a scanning tunnelling microscope, we measure the ultrafast collective dynamics of the charge density wave in the transition metal dichalcogenide 2H-NbSe₂ with atomic spatial resolution. The tip-enhanced electric field of the terahertz pulses excites oscillations of the charge density wave that vary in magnitude and frequency on the scale of individual atomic impurities. Overlappin

SUBMITTER: Sheng S 

PROVIDER: S-EPMC11473363 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature