Europhys. Lett.
Volume 65, Number 2, January 2004
Page(s) 158 - 164
Section General
Published online 01 January 2004
Europhys. Lett., 65 (2) , pp. 158-164 (2004)
DOI: 10.1209/epl/i2003-10064-8

Macroscopic quantum effects in nanomechanical systems

P. Werner1 and W. Zwerger1, 2

1  Center for NanoScience and Sektion Physik, Ludwig-Maximilians-Universität Theresienstr. 37, D-80333 München, Germany
2  Institute for Theoretical Physics, University of Innsbruck Technikerstr. 25, A-6020 Innsbruck, Austria

(Received 28 July 2003; accepted in final form 3 November 2003)

We investigate quantum effects in the mechanical properties of elastic beams on the nanoscale. Transverse quantum and thermal fluctuations and the nonlinear excitation energies are calculated for beams compressed in longitudinal direction. Near the Euler instability, the system is described by a one-dimensional Ginzburg-Landau model, where the order parameter is the amplitude of the buckling mode. We show that in single-wall carbon nanotubes with lengths of the order of or smaller than 100 $\un{nm}$, zero-point fluctuations are accessible, and discuss the possibility of observing macroscopic quantum coherence in nanobeams near the critical strain.

03.65.-w - Quantum mechanics.
62.25.+g - Mechanical properties of nanoscale materials.
62.30.+d - Mechanical and elastic waves; vibrations.

© EDP Sciences 2004