Related Experiment Video
Updated: Aug 13, 2026
09:20
Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology
Published on: December 7, 2015
Discontinuous tangential stress in double wall carbon nanotubes
P Puech1, H Hubel, D J Dunstan
1Laboratoire Physique des Solides de Toulouse UMR-CNRS 5477, IRSAMC, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse, France. Pascal.Puech@lpst.ups-tlse.fr
Physical Review Letters
|September 28, 2004
Summary
We studied double wall carbon nanotubes under high pressure. The inner tube shows less stress response and stable phonon bands, unlike the outer tube, explained by a new elastic model.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Double-wall carbon nanotubes (DWCNTs) are advanced nanomaterials with unique mechanical and electronic properties.
- Understanding their behavior under extreme conditions, such as high hydrostatic pressure, is crucial for potential applications.
Purpose of the Study:
- To investigate the stability and mechanical response of DWCNTs under hydrostatic pressures up to 10 GPa.
- To analyze the pressure-dependent behavior of phonon modes in both the inner and outer tubes of DWCNTs.
Main Methods:
- Inelastic light scattering was employed to observe the tangential optical phonon mode.
- Hydrostatic pressures up to 10 GPa were applied to the DWCNT samples.
- The elastic continuum shell model was utilized to interpret the experimental results.
Main Results:
- The tangential optical phonon mode splits, showing distinct responses for the external and internal tubes.
- The internal tube exhibits a 45% smaller pressure coefficient compared to the external tube and single-wall carbon nanotubes.
- The external tube's phonon band broadens with pressure, while the internal tube's remains constant.
Conclusions:
- The contrasting pressure responses of the inner and outer tubes are attributed to distinct stress components.
- The elastic continuum shell model successfully explains the observed pressure-dependent phonon shifts and line broadening.
- These findings provide insights into the mechanical properties and stability of DWCNTs under pressure.
Related Concept Videos
01:16Stress on an Oblique Plane
Understanding stress on an oblique plane under axial loading is pivotal in material mechanics. This analysis offers insight into a material's durability and strength, which is crucial for civil engineering and structural design. Axial loading refers to force application along the material's central axis, causing compression or elongation and leading to normal stress. Normal stress occurs when a force acts perpendicularly to the material's area, resulting in compressive or tensile stress. When...
01:24Stress-Strain Diagram - Ductile Materials
The stress-strain relationship in ductile materials such as structural steel or aluminium is intricate and progresses through several stages. When a specimen is loaded, it initially exhibits a linear length increase, depicted by a steep straight line on the stress-strain diagram. It indicates the material is elastically deforming and will return to its original shape once unloaded. However, when a critical stress value is reached, plastic deformation begins. This stage sees substantial...
01:10Residual Stresses in Circular Shafts
In materials that exhibit elastic and plastic behavior, known as elastoplastic materials, residual stresses can accumulate when these materials experience plastic deformation. This deformation arises from either high levels of shearing stress or significant strains. Residual stresses are internal stresses that persist within a material after removing the external force causing deformation. This phenomenon is demonstrated when observing the behavior of a shaft under torque; notably, the shaft's...
01:16Torsion of Noncircular Members
Circular shafts undergoing torsional stress maintain their cross-sectional integrity due to their axisymmetric nature. This symmetry ensures an even distribution of stress, allowing the shaft to withstand torsion without distorting. In contrast, square bars, lacking this axial symmetry, experience significant distortion across their cross-sections when subjected to torsion, with the exception of along their diagonals and at lines connecting midpoints. A detailed examination of a cubic element...
01:15Thin-Walled Hollow Shafts
In analyzing a thin-walled hollow shaft subjected to torsional loading, a segment with width dx is isolated for examination. Despite its equilibrium state, this segment faces torsional shearing forces at its ends. These forces are quantitatively described by the product of the longitudinal shearing stress on the segment's minor surface and the area of this surface, leading to the concept of shear flow. This shear flow is consistent throughout the structure, indicating a uniform distribution of...
01:23Stresses under Combined Loadings
When analyzing a bent tube with a circular cross-section subjected to multiple forces, it is crucial to determine the stress distribution in order to maintain structural integrity under varied load conditions.
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...