Prediction for the Flexural Properties of Nanowires in Lateral Manipulation

Simple beam theory is usually employed to predict the flexural properties of nanowires (NWs) in the lateral manipulation, which results in a linear curve. However, three factors, namely, changes in the load position and direction of the AFM tip, surface effects, and the large displacement of the NW, are not considered in simple beam theory. In this work, a simple geometrical model is proposed to analyze the large deflection and rotational angle deformation of NWs in the lateral manipulation. The traditional solution to the differential equation of the deflection curve turns the solution of an integral equation. Results show that contact force does not linearly increase with increasing displacement, and the curve exists a maximum amount due to changes in the load position and direction of the AFM tip. Moreover, the rotational angle and deflection have a nonlinear relationship. Comparison of the results of this work with other authors’ measurements illustrates that the use of simple beam theory in manipulation underestimates the deflection and effective modulus of NWs. Our model provides a good approach to predict curves, rotational angles, and contact forces that closely match experimental results.