Sliding nanomechanical resonators

TL;DR

This paper investigates nanomechanical resonators with sliding boundary conditions, revealing complex vibrational dynamics and hysteresis effects, which could advance nanoscale friction studies and tunable resonator applications.

Contribution

It demonstrates the first experimental observation of sliding motion in nanomechanical resonators and explores its impact on vibrational frequency behavior.

Findings

Resonant frequency loops with gate voltage cycling

Delayed frequency response indicating complex dynamics

Potential for nanoscale friction studies

Abstract

The motion of a vibrating object is determined by the way it is held. This simple observation has long inspired string instrument makers to create new sounds by devising elegant string clamping mechanisms, whereby the distance between the clamping points is modulated as the string vibrates. At the nanoscale, the simplest way to emulate this principle would be to controllably make nanoresonators slide across their clamping points, which would effectively modulate their vibrating length. Here, we report measurements of flexural vibrations in nanomechanical resonators that reveal such a sliding motion. Surprisingly, the resonant frequency of vibrations draws a loop as a tuning gate voltage is cycled. This behavior indicates that sliding is accompanied by a delayed frequency response of the resonators, making their dynamics richer than that of resonators with fixed clamping points. Our work elucidates the dynamics of nanomechanical resonators with unconventional boundary conditions, and offers opportunities for studying friction at the nanoscale from resonant frequency measurements.