Fatemeh Sadeghi - Assistant Professor, Department of Engineering Sciences, Faculty of AdvancedTechnologies, University of Mohaghegh Ardabili, ۵۶۳۱۸-۴۴۱۳۳, Namin, Iran

This paper deals with the van der Waals (vdW) interactions and oscillatory motion of nestedspherical fullerenes, known as carbon onions, in the vicinity of a single layer graphene (SLG)sheet. The carbon onions are of Ih symmetries and the graphene sheet is modeled as a fullyconstrained flat surface. Utilizing the continuum approximation in conjunction with the ۶-۱۲Lennard-Jones (LJ) potential function, explicit analytical expressions are derived to evaluatethe vdW potential energy and interaction force. The equation of motion is solved numericallyto attain the time histories of displacement and velocity of the carbon onion. On the basis ofconservation of mechanical energy principle, a semi-analytical expression is also derived toaccurately evaluate the oscillation frequency. Numerical results are presented to examine theinfluences of size of carbon onion and initial conditions (initial separation distance and initialvelocity) on the operating frequency of carbon onion-SLG sheet oscillators. It is shown thatcarbon onion performs oscillatory motion above the graphene sheet with frequencies in thegigahertz (GHz) range. It is further observed that smaller structures of carbon onions producegreater frequencies. The presented results in this study would contribute to the developmentof new generation of nano-oscillators.

graphene sheet; carbon onion; continuum approximation; oscillation frequency