Resonant frequency-based method for measuring the Young’s moduli of nanowires

The electric-field-induced resonance method [Poncharal et al., Science 283, 5 (1999)] has been widely applied to measure the Young's moduli of nanowires. In the present paper, a systematic study of the effects of various clamp uncertainties (partially pinned, elastic foundation, unknown defects, etc.) on the Young's moduli determined with this method, shows that those effects cannot be ignored in the nanoscale. Inspired by string instruments, we propose a simple method to remedy this shortcoming, i.e., adding an extra support to the nanowire cantilever to change the resonant frequencies. It is demonstrated that by use of this method all clamp uncertainties can be effectively filtered out and the Young's moduli can be precisely determined through measuring only a few fundamental resonant frequencies of the extra supported nanowire cantilever.