Issue
EPL
Volume 78, Number 6, June 2007
Article Number 60002
Number of page(s) 6
Section General
DOI http://dx.doi.org/10.1209/0295-5075/78/60002
Published online 24 May 2007
EPL, 78 (2007) 60002
DOI: 10.1209/0295-5075/78/60002

Dissipation due to two-level systems in nano-mechanical devices

C. Seoanez1, F. Guinea1 and A. H. Castro Neto2, 3

1  Instituto de Ciencia de Materiales de Madrid, CSIC - Cantoblanco, E28049 Madrid, Spain
2  Department of Physics, Harvard University - Cambridge, MA 02138, USA
3  Department of Physics, Boston University - 590 Commonwealth Avenue, Boston, MA 02215, USA


received 13 February 2007; accepted in final form 2 May 2007; published June 2007
published online 24 May 2007

Abstract
We analyze the dissipation of the vibrations of nano-mechanical devices. We show that the coupling between flexural modes and two-level systems leads to sub-ohmic dissipation. The inverse quality factor of the flexural modes of low frequencies depends on temperature as $Q^{-1} ( T) \approx Q_{0}+CT^{1/3}$, providing a quantitative description of the experimental data.

PACS
03.65.Yz - Decoherence; open systems; quantum statistical methods.
62.40.+i - Anelasticity, internal friction, stress relaxation, and mechanical resonances.
85.85.+j - Micro- and nano-electromechanical systems (MEMS/NEMS) and devices.

© Europhysics Letters Association 2007