Ultrasensitive charge detection utilizing coupled nonlinear micromechanical resonators

TL;DR

This paper presents a novel charge detection method using coupled nonlinear micromechanical resonators, achieving ultra-high sensitivity at room temperature, and offering a simpler, more practical electrometer design.

Contribution

It introduces a new charge detection technique based on frequency drift in coupled nonlinear resonators, enabling high accuracy without complex setups.

Findings

Achieved 2.051E-3 fC charge resolution at room temperature.

Demonstrated application for ultra-low-frequency signal detection.

Provided a simple strategy for precise electron charge measurement.

Abstract

Since the discovery of electrons, an accurate detection of electrical charges has been the dream of scientific community. Due to some remarkable advantages, micro/nano-electromechanical systems (M/NEMS) based resonators have been used to design electrometers with exquisite sensitivity and resolution. Inevitably, some limits including requisite ultra-low environmental temperature, complicated resonator structure and measurement circuit, required linear dynamic response, will cause a gap with respect to practical application. Here, we demonstrate a novel ultra-sensitive charge detection based on the linear dependence of peak frequency drift on the coupling voltage variation of two coupled nonlinear micromechanical resonators. We achieved ultra-high resolution of 2.051E-3 fC (about 13 electrons) of charge detection at the room temperature. We also show an extra application of this device for weak and ultra-low-frequency (ULF) signal detection. Our findings provide a simple strategy for measuring electron charges in an extreme accuracy and developing electrometers in smaller sizes.