Dissipation in Nanocrystalline-Diamond Nanomechanical Resonators

TL;DR

This study investigates dissipation mechanisms in nanocrystalline-diamond nanomechanical resonators across a broad temperature range, revealing a weak temperature dependence and a thermally activated dissipation feature.

Contribution

It introduces a novel time-domain ring-down technique and provides detailed measurements of dissipation and frequency in nanocrystalline diamond resonators.

Findings

Dissipation follows approximately T^0.2 dependence.

Q^-1 is about 10^-4 at low temperatures.

A dissipation feature at 35-55 K is consistent with thermal activation over a 0.02 eV barrier.

Abstract

We have measured the dissipation and frequency of nanocrystalline-diamond nanomechanical resonators with resonant frequencies between 13.7 MHz and 157.3 MHz, over a temperature range of 1.4-274 K. Using both magnetomotive network analysis and a novel time-domain ring-down technique, we have found the dissipation in this material to have a temperature dependence roughly following T^0.2, with Q^-1 = 10^-4 at low temperatures. The frequency dependence of a large dissipation feature at ~35-55 K is consistent with thermal activation over a 0.02 eV barrier with an attempt frequency of 10 GHz.