Theory of noncontact friction for atom-surface interactions

Abstract

The noncontact (van der Waals) friction is an interesting physical effect which has been the subject of controversial scientific discussion. The "direct" friction term due to the thermal fluctuations of the electromagnetic field leads to a friction force proportional to 1/Z^5 where Z is the atom-wall distance). The "backaction" friction term takes into account the feedback of thermal fluctuations of the atomic dipole moment onto the motion of the atom and scales as 1/Z^8. We investigate noncontact friction effects for the interactions of hydrogen, ground-state helium and metastable helium atoms with alpha-quartz (SiO_2), gold (Au) and calcium difluorite (CaF_2). We find that the backaction term dominates over the direct term induced by the thermal electromagnetic fluctuations inside the material, over wide distance ranges. The friction coefficients obtained for gold are smaller than those for SiO_2 and CaF_2 by several orders of magnitude.

11 pages; ReVTeX

References in corpus (11)

• Radiative heat transfer between nanostructures
• Theory of friction: contribution from fluctuating electromagnetic field
• Dissipative Van der Waals interaction between a small particle and a metal surface
• Non-contact friction between nanostructures
• Adsorbate induced enhancement of electrostatic non-contact friction
• Quantum field theory of the van der Waals friction
• Enhancement of Blackbody Friction due to the Finite Lifetime of Atomic Levels
• One-Loop Dominance in the Imaginary Part of the Polarizability: Application to Blackbody and Non-Contact van der Waals Friction
• Temperature dependence of the dielectric permittivity of CaF2, BaF2 and Al2O3: application to the prediction of a temperature dependent van der Waals surface interaction exerted onto a neighbouring Cs (8P{3/2}) atom
• Functional Form of the Imaginary Part of the Atomic Polarizability
• Non-Contact Friction for Ion-Surface Interactions

Cited by in corpus (4)

• Temperature-dependent dielectric function of intrinsic silicon: Analytic models and atom-surface potentials
• Electromagnetic Viscosity in Complex Structured Environments: From black-body to Quantum Friction
• Nonequilibrium Casimir-Lifshitz force and anomalous radiation heating of a small particle
• Revisiting the Divergent Multipole Expansion of Atom-Surface Interactions: Hydrogen and Positronium, alpha-Quartz, and Physisorption