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It is noted that an oscillator from a curved double-walled nanotube can provide a local stronger periodic adjustable magnetic field than that from a straight double-walled carbon nanotube when the inner tube loses electric neutrality at the ends. Therefore, it is interesting to study the damped rotational and oscillatory behavior of curved double-wall carbon nanotubes (DWCNTs) through a molecular dynamics (MD) simulation approach. As the outer tube is curved, intuitionally, the intertube friction becomes stronger. Hence, the rotational and oscillatory characteristics of a single-wall carbon nanotube (SWCNT) within a curved outer tube might be obviously different from those of SWCNTs within straight DWCNTs. To investigate the effects of curvature on dynamic behavior, a straight (9, 9)/(14, 14) DWCNT is geometrically mapped into three curved bitube systems with different curvatures. In the microcanonical NVE ensemble, the inner tube with initial high speed rotation has damped rotation and oscillation along the curved axis of the outer tube. Energy transfer between two curved tubes is faster than that between two straight tubes. Further, the oscillation of the inner tube is disordered when the curvature is relatively high. The rotational frequency of an inner tube in a curved outer tube decreases more quickly than that in a straight outer tube. Effects of temperature on dynamic behavior of curved double-walled nanotubes are also investigated through a numerical example. |
