Frequency stabilization in nonlinear nanomechanical oscillators

May 28, 2012

Using Center for Nanoscale Materials (CNM) expertise in the design and fabrication of micro- and nanoscale devices, a new strategy for engineering low-frequency noise oscillators capitalizes on the intrinsic nonlinear phenomena of micro- and nanomechanical resonators. A fundamental limitation of such resonators was addressed by a team of researchers from the Nanofabrication & Devices Group working with CNICT, Argentina.

Mechanical oscillators are an essential component of nearly every electronic system requiring a frequency reference for timekeeping or synchronization. They are also widely used in frequency-shift-based sensors of mass, force, and magnetic field. Unfortunately, as the dimensions of vibrating semiconductor structures are reduced to the micro- and nanoscale, their dynamic response at the amplitudes needed for operation frequently becomes nonlinear.

In addition, large displacement instabilities and excessive frequency noise considerably degrade their performance. In this regime, unlike the linear case, the resonant frequency has a strong dependence with the oscillation amplitude. This increases frequency noise of the oscillator considerably, and thus, the benefits of operating at higher amplitudes are undone.

The limitation was overcome by coupling two different vibrational modes through an internal resonance, where the energy exchange between modes is such that the resonance of one mode absorbs the amplitude and frequency fluctuations of the other. This effectively acts as a stabilizing mechanical negative feedback loop.

The result demonstrates that very low-frequency noise performance is possible in the nonlinear regime and provides a path to replace quartz oscillators with nanoelectromechanical systems technology.

Explore further: Scientists use simple, low cost laser technique to improve properties and functions of nanomaterials

More information: D. Antonio, et al. (CNM), "Frequency stabilization in nonlinear micromechanical oscillators," Nature Communications, 3, 806 (2012) [doi: 10.1038/ncomms1813]

add to favorites email to friend print save as pdf

Related Stories

New sensor exploits traditional weakness of nano devices

Feb 12, 2010

By taking advantage of a phenomenon that until now has been a virtual showstopper for electronics designers, a team led by Oak Ridge National Laboratory's Panos Datskos is developing a chemical and biological sensor with ...

Exotic behavior when mechanical devices reach the nanoscale

May 15, 2011

Most mechanical resonators damp (slow down) in a well-understood linear manner, but ground-breaking work by Prof. Adrian Bachtold and his research group at the Catalan Institute of Nanotechnology has shown that resonators ...

Recommended for you

PPPL studies plasma's role in synthesizing nanoparticles

Jul 22, 2014

DOE's Princeton Plasma Physics Laboratory (PPPL) has received some $4.3 million of DOE Office of Science funding, over three years, to develop an increased understanding of the role of plasma in the synthesis ...

First ab initio method for characterizing hot carriers

Jul 17, 2014

One of the major road blocks to the design and development of new, more efficient solar cells may have been cleared. Researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) have developed ...

User comments : 0