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Title: Giant enhancement of noncontact friction between closely spaced bodies by dielectric films and two-dimensional systems

Abstract

The effect of an external bias voltage and spatial variations of the surface potential on the damping of cantilever vibrations in an atomic force microscope (AFM) is considered. The damping is due to an electrostatic friction that arises due to dissipation of the energy of an electromagnetic field generated in the sample by oscillating static charges induced on the surface of the AFM probe tip by the bias voltage or spatial variations of the surface potential. A similar effect appears when the tip is oscillating in an electrostatic field created by charged defects present in the dielectric sample. The electrostatic friction is compared to the van der Waals (vdW) friction between closely spaced bodies, which is caused by a fluctuating electromagnetic field related to the quantum and thermal fluctuations of current density inside the bodies. It is shown that the electrostatic friction and the vdW friction can be strongly enhanced in the presence of dielectric films or two-dimensional (2D) structures-such as a 2D electron system or an incommensurate layer of adsorbed ions exhibiting acoustic oscillations-on the probe tip and sample surfaces. It is also shown that the damping of cantilever oscillations caused by the electrostatic friction in the presence ofmore » such 2D structures can have the same order of magnitude and the same dependence on the distance as observed in experiment by Stipe et al. [Phys. Rev. Lett. 87, 096801 (2001)]. At small distances, the vdW friction can be large enough to be measured in experiment. In interpreting the experimental data that obey a quadratic dependence on the bias voltage, one can reject a phonon mechanism according to which the friction depends on the fourth power of the voltage.« less

Authors:
;  [1];  [2]
  1. Forschungszentrum Juelich, Institut fuer Festkoerperforschung (Germany)
  2. Toyama University, Department of Electronics (Japan)
Publication Date:
OSTI Identifier:
21072548
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 104; Journal Issue: 1; Other Information: DOI: 10.1134/S1063776107010116; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMIC FORCE MICROSCOPY; CURRENT DENSITY; DIELECTRIC MATERIALS; ELECTRIC POTENTIAL; ELECTROMAGNETIC FIELDS; ELECTRONS; EXPERIMENTAL DATA; FILMS; FLUCTUATIONS; FRICTION; OSCILLATIONS; PHONONS; SURFACE POTENTIAL; TWO-DIMENSIONAL CALCULATIONS; VAN DER WAALS FORCES

Citation Formats

Volokitin, A. I., E-mail: avoli@samgtu.ru, Persson, B. N. J., and Ueba, H. Giant enhancement of noncontact friction between closely spaced bodies by dielectric films and two-dimensional systems. United States: N. p., 2007. Web. doi:10.1134/S1063776107010116.
Volokitin, A. I., E-mail: avoli@samgtu.ru, Persson, B. N. J., & Ueba, H. Giant enhancement of noncontact friction between closely spaced bodies by dielectric films and two-dimensional systems. United States. doi:10.1134/S1063776107010116.
Volokitin, A. I., E-mail: avoli@samgtu.ru, Persson, B. N. J., and Ueba, H. Thu . "Giant enhancement of noncontact friction between closely spaced bodies by dielectric films and two-dimensional systems". United States. doi:10.1134/S1063776107010116.
@article{osti_21072548,
title = {Giant enhancement of noncontact friction between closely spaced bodies by dielectric films and two-dimensional systems},
author = {Volokitin, A. I., E-mail: avoli@samgtu.ru and Persson, B. N. J. and Ueba, H.},
abstractNote = {The effect of an external bias voltage and spatial variations of the surface potential on the damping of cantilever vibrations in an atomic force microscope (AFM) is considered. The damping is due to an electrostatic friction that arises due to dissipation of the energy of an electromagnetic field generated in the sample by oscillating static charges induced on the surface of the AFM probe tip by the bias voltage or spatial variations of the surface potential. A similar effect appears when the tip is oscillating in an electrostatic field created by charged defects present in the dielectric sample. The electrostatic friction is compared to the van der Waals (vdW) friction between closely spaced bodies, which is caused by a fluctuating electromagnetic field related to the quantum and thermal fluctuations of current density inside the bodies. It is shown that the electrostatic friction and the vdW friction can be strongly enhanced in the presence of dielectric films or two-dimensional (2D) structures-such as a 2D electron system or an incommensurate layer of adsorbed ions exhibiting acoustic oscillations-on the probe tip and sample surfaces. It is also shown that the damping of cantilever oscillations caused by the electrostatic friction in the presence of such 2D structures can have the same order of magnitude and the same dependence on the distance as observed in experiment by Stipe et al. [Phys. Rev. Lett. 87, 096801 (2001)]. At small distances, the vdW friction can be large enough to be measured in experiment. In interpreting the experimental data that obey a quadratic dependence on the bias voltage, one can reject a phonon mechanism according to which the friction depends on the fourth power of the voltage.},
doi = {10.1134/S1063776107010116},
journal = {Journal of Experimental and Theoretical Physics},
number = 1,
volume = 104,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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