Document Detail

Noncontact friction and relaxational dynamics of surface defects.
MedLine Citation:
PMID:  22540716     Owner:  NLM     Status:  In-Data-Review    
The motion of a cantilever near sample surfaces exhibits additional friction even before two bodies come into mechanical contact. Called noncontact friction (NCF), this friction is of great practical importance to the ultrasensitive force detection measurements. The observed large NCF of a micron-scale cantilever found an anomalously large damping that exceeds theoretical predictions by 8-11 orders of magnitude. This finding points to a contribution beyond fluctuating electromagnetic fields within the van der Waals approach. Recent experiments reported by Saitoh et al. [Phys. Rev. Lett. 105, 236103 (2010)] also found a nontrivial distance dependence of NCF. Motivated by these observations, we propose a mechanism based on the coupling of a cantilever to the relaxation dynamics of surface defects. We assume that the surface defects couple to the cantilever tip via spin-spin coupling and their spin relaxation dynamics gives rise to the backaction terms and modifies both the friction coefficient and the spring constant. We explain the magnitude, as well as the distance dependence of the friction due to these backaction terms. Reasonable agreement is found with the experiments.
Jian-Huang She; Alexander V Balatsky
Related Documents :
10641636 - Modeling of subcritical penetration into sediments due to interface roughness
11970286 - Doppler shift anisotropy in small angle neutron scattering.
17348496 - Comment on "analysis of the time-reversal operator for scatterers of finite size," by d...
18264396 - Single-particle scattering effects on the resonance modes of microdroplets.
9641906 - Plasticity induced by shock waves in nonequilibrium molecular-dynamics simulations
12606996 - Logarithmic rate dependence of force networks in sheared granular materials.
Publication Detail:
Type:  Journal Article     Date:  2012-03-28
Journal Detail:
Title:  Physical review letters     Volume:  108     ISSN:  1079-7114     ISO Abbreviation:  Phys. Rev. Lett.     Publication Date:  2012 Mar 
Date Detail:
Created Date:  2012-04-30     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0401141     Medline TA:  Phys Rev Lett     Country:  United States    
Other Details:
Languages:  eng     Pagination:  136101     Citation Subset:  IM    
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Charge redistribution mechanisms of ceria reduction.
Next Document:  Incoherent scatterer in a luttinger liquid: a new paradigmatic limit.