Microscopic evidence for strong periodic lattice distortion in 2D charge-density wave systems

Abstract

In the quasi-2D electron systems of the layered transition metal dichalcogenides (TMD) there is still a controversy about the nature of the transitions to charge-density wave (CDW) phases, i.e. whether they are described by a Peierls-type mechanism or by a lattice-driven model. By performing scanning tunneling microscopy (STM) experiments on the canonical TMD-CDW systems, we have imaged the electronic modulation and the lattice distortion separately in 2H-TaS${}_2$, TaSe${}_2$, and NbSe${}_2$. Across the three materials, we found dominant lattice contributions instead of the electronic modulation expected from Peierls transitions, in contrast to the CDW states that show the hallmark of contrast inversion between filled and empty states. Our results imply that the periodic lattice distortion (PLD) plays a vital role in the formation of CDW phases in the TMDs and illustrate the importance of taking into account the more complicated lattice degree of freedom when studying correlated electron systems.

References in corpus (6)

• Fermi surface nesting and the origin of Charge Density Waves in metals
• Electrical Tuning of Valley Magnetic Moment via Symmetry Control
• Two energy gaps and Fermi surface 'arcs' in NbSe2
• Pseudogap and charge density waves in two dimensions
• A quantum phase transition from triangular to stripe charge order in NbSe${}_2$
• Tuning the Charge Density Wave and Superconductivity in CuxTaS2

Cited by in corpus (26)

• Electronic structure of $2H$-NbSe${}_2$ single-layers in the CDW state
• Charge Order in the Holstein Model on a Honeycomb Lattice
• Interplay of electron-electron and electron-phonon interactions in the low temperature phase of 1T-TaS2
• Yu-Shiba-Rusinov states in the charge-density modulated superconductor NbSe2
• Quantum spins and hybridization in artificially-constructed chains of magnetic adatoms on a superconductor
• Topological Landscape of Competing Charge Density Waves in 2H-NbSe2
• Insight into the charge density wave gap from contrast inversion in topographic STM images
• Direct Visualization of Trimerized States in 1T'-TaTe${}_2$
• Orbital selectivity causing anisotropy and particle-hole asymmetry in the charge density wave gap of $2H$-TaS${}_2$
• Real-Space Investigation of the Charge Density Wave in VTe2 Monolayer with Rotational and Mirror Symmetries Broken
• Energy-dependent spatial texturing of the charge order in $1T$-Cu${}_x$TiSe${}_2$
• Multiple Charge Density Wave States at the Surface of TbTe${}_3$
• Interplay between multiple charge-density waves and the relationship with superconductivity in Pd${}_x$HoTe${}_3$
• Interplay of charge density waves, disorder, and superconductivity in 2$H$-TaSe${}_2$ elucidated by NMR
• Manipulating Hubbard-type Coulomb blockade effect of metallic wires embedded in an insulator
• Charge-Density Waves vs. Superconductivity: Some Results and Future Perspectives
• Structural versus electronic distortions of symmetry-broken IrTe${}_2$
• Absence of in-gap modes in charge density wave edge dislocations of the Weyl semimetal (TaSe${}_4$)${}_2$I
• Melting of unidirectional charge density waves across twin domain boundaries in GdTe${}_3$
• Moiré Superstructures in Marginally-Twisted NbSe${}_2$ Bilayers
• Fermi surface of IrTe2 in the valence-bond state as determined by quantum oscillations
• Bulk Electronic Structure of Ni2MnGa studied by Density Functional Theory and Hard X-ray Photoelectron Spectroscopy
• Charge Orders in Fully Intercalated Bilayer TaSe${}_2$: Dependence on Interlayer Stacking and Intercalation Sites
• Influence of surface relaxations on scanning probe microscopy images of the charge density wave material 2H-NbSe${}_2$
• Feedback loop dependent charge density wave imaging by scanning tunneling spectroscopy
• Interplay of charge density wave and multiband superconductivity in 2$H$-Pd${}_x$TaSe${}_2$