Doubly-Clamped Single Walled Boron Nitride Nanotube Based Nanomechanical Resonators: A Computational Investigation of Their Behavior

This paper illustrates the dynamic behavior of a doubly-clamped single walled boron nitride nanotube (SWBNNT) as a mass sensor. To this end, a 3-dimensional atomistic model based on molecular structural mechanics is developed such that the proximity of the model to the actual atomic structure of the nanotube is significantly retained. Different types of zigzag and armchair layouts of SWBNNTs are considered with doubly-clamped end constraints. Implementing the finite element simulation approach, the resonant frequency shift based analysis is performed for doubly-clamped end-constraints, for an additional nanoscale mass at the middle of the length, and at the intermediate landing position along the length of the nanotube. The effect of the intermediate landing position of added mass on the resonant frequency shift is analyzed by considering excitations of the fundamental modes of vibration. The finite element method (FEM) based simulation results are validated using the continuum mechanics based analytical results, considering the effective wall thickness of the SWBNNT. The present approach is found to be effectual in terms of dealing with different chiralities, boundary conditions, and the consideration of the added mass to analyze the dynamic behavior of the doubly-clamped SWBNNT based nanomechanical resonators.