CDW slips and giant frictional dissipation peaks at the NbSe${}_2$ surface

Abstract

Accessing, controlling and understanding nanoscale friction and dissipation is a crucial issue in nanotechnology, where moving elements are central. Recently, ultra-sensitive noncontact pendulum Atomic Force Microscope (AFM) succeeded in detecting the electronic friction drop caused by the onset of superconductivity in Nb, raising hopes that a wider variety of mechanisms of mechanical dissipation arising from electron organization into different collective phenomena will become accessible through this unconventional surface probe. Among them, the driven phase dynamics of charge-density-waves (CDWs) represents an outstanding challenge as a source of dissipation. Here we report a striking multiplet of AFM dissipation peaks arising at nanometer distances above the surface of NbSe${}_2$ - a layered compound exhibiting an incommensurate CDW. Each peak appears at a well defined tip-surface interaction force of the order of a nN, and persists until T=70K where CDW short-range order is known to disappear. A theoretical model is presented showing that the peaks are connected to tip-induced local 2$\pi$ CDW phase slips. Under the attractive potential of the approaching tip, the local CDW surface phase landscape deforms continuously until a series of 2$\pi$ jumps occur between different values of the local phase. As the tip oscillates to and fro, each slip gives rise to a hysteresis cycle, appearing at a selected distance, the dissipation corresponding to "pumping" in and out a local slip in the surface CDW phase of NbSe${}_2$.

arXiv comment9 pages, 8 figures

References in corpus (10)

• Modeling friction: From nanoscale to mesoscale
• Extended Phonon Collapse and the Origin of the Charge-Density-Wave in NbSe${}_2$
• Superconducting density of states and vortex cores of 2H-NbS2
• Two energy gaps and Fermi surface 'arcs' in NbSe2
• A quantum phase transition from triangular to stripe charge order in NbSe${}_2$
• Fermi surface nesting in several transition metal dichalcogenides
• Primary role of the barely occupied states in the charge density wave formation of NbSe2
• Gigantic Maximum of Nanoscale Noncontact Friction
• Non-contact Friction and Relaxational Dynamics of Surface Defects
• Visualizing the Charge Density Wave Transition in 2H-NbSe2 in Real Space

Cited by in corpus (12)

• A Rigorous Method of Calculating Exfoliation Energies from First Principles
• Yu-Shiba-Rusinov states in the charge-density modulated superconductor NbSe2
• Lateral vibration effects in atomic-scale friction
• Joule meets van der Waals: Mechanical dissipation via image potential states on a topological insulator surface
• Mechanical dissipation from charge and spin transitions in oxygen deficient SrTiO_3
• Ballistic thermophoresis of adsorbates on free-standing graphene
• Current trends in the physics of nanoscale friction
• From chiral anomaly to two-fluid hydrodynamics for electronic vortices
• Charge density wave surface phase slips and non-contact nanofriction
• Mechanical dissipation at a tip-induced Kondo onset
• Kondo nanomechanical dissipation in the driven Anderson impurity model
• Enhancement of non-contact friction between metal surfaces induced by the electrical double layer