arXiv subjects

Quanshui Zheng

Publications and source records attributed to Quanshui Zheng.

39 records · Page 3Linked to original sources

arXiv2007

Trans-phonon effects in ultrafast nano-devices

We report a novel phenomenon in carbon nanotube (CNT) based devices, the transphonon effects, which resemble the transonic effects in aerodynamics. It is caused by dissipative resonance of nanotube phonons similar to the radial breathing mode, and subsequent drastic surge of the dragging force on the sliding tube, and multiple phonon barriers are encountered as the intertube sliding velocity reaches critical values. It is found that the transphonon effects can be tuned by applying geometric constraints or varying chirality combinations of the nanotubes.

cond-mat.mtrl-sci↗

arXiv2006

Nanomachines driven by thermal bath

Multiwalled carbon nanotubes based nanomachines driven by thermal bath are proposed in this Letter. Atomistic simulation shows that intershell translational and rotational motion can be activated at sufficiently high temperature, where the van der Waals potential barrier is accessible by the thermal fluctuation. The thermal fluctuation is further identified to be consistent with the equipartition theorem. This model can be used to construct one dimensional devices driven by thermal bath or nano-channels for molecule transport.

cond-mat.stat-mech↗

arXiv2006

Condensed Multiwalled Carbon Nanotubes as Super Fibers

The ultra-low intershell shear strength in carbon nanotubes (CNTs) has been the primary obstacle to applications of CNTs as mechanical reinforcements. In this paper we propose a new CNT-system composed of comprising of coaxial cylindrical shells of sp2-bonded carbons with condensed intershell spacings. Our atomistic calculations show that such condensed multiwalled carbon nanotubes (CMWNTs) can greatly enhance intershell shear strengths by several orders, and can simultaneously generate higher tensile strengths and moduli respectively than those of ordinary CNTs. It has further shown that CMWNTs can maintain thermally stable up to 2,000 K. By taking advantage of the primary enhancement mechanism of CMWNTs, a method of producing CMWNTs is therefore proposed tentatively. It is believed that CMWNTs featured with those properties can be taken as excellent candidates of super fibers for creating space elevators.

cond-mat.mtrl-sci↗