In partial fulfillment of the requirements for the degree of doctor of philosophy. Dielectric resonator oscillators dros are microwave oscillators that use a dielectric resonator dr as the frequency stabilizing element in order to achieve excellent frequency stability, high q and very low microphonics. Energy dissipation is a key ingredient in understanding many physical phenomena in thermodynamics, photonics, chemical reactions, nuclear fission, photon emissions, or. Barnhart abstract over the past decade there has been an explosion in the demand for wireless mobile personal communications systems pcs, a trend that shows no signs of slowing down in the foreseeable future. This tension can be controlled by adjusting the axial strain of the string or deflecting the. Performance of monolayer graphene nanomechanical resonators with electrical readout changyao chen, sami rosenblatt, kirill i. Unfortunately, the mass sensitivity of cnt resonators is impeded by the low quality factor q caused by intrinsic losses. Electron pumping in graphene mechanical resonators. Micronanoelectromechanical systems mnems resonators. Symmetry breaking in a mechanical resonator made from a. In this work, we present data from three different types of resonators. The key challenges associated with the development of high performance mems and nems resonators for rf wireless communication and sensing applications are the isolation of energydissipating mechanisms and scaling of the device volume in the nanoscale sizerange. Largescale arrays of singlelayer graphene resonators. Guaranteed by the superior electrical and excellent me.
The dr, when used as part of the resonating circuit of. Therefore, one should minimize dissipations or seek an external way to enhance q in. Nonlinear damping in mechanical resonators made from. To avoid these problems with polymer contamination and explore the possibility of controlling the tension in our devices, we have developed a novel method for the fabrication of graphene membranes. Graphene nanoelectromechanical resonators and oscillators. The resonators were selfsensing silicon nitride nanocantilevers figure 1a that had an integrated piezoresistive readout. Microcontroller clock rc oscillator, crystal or resonator. Electromechanical switch devices employing suspended graphene as movable elements have been developed. Mnems resonators have been used in a variety of different ways to implement various sensor systems on chip, including temperature and pressure sensors, timing elements, inertial sensors including accelerometers, gyroscopes and magnetometers, and gas and chemical sensors, among other physical quantities of interest. This demand has created a greater need for lowcost. Graphene opens up new applications for microscale resonators.
Pdf graphene mechanical oscillators with tunable frequency. Frequency tuning of graphene nanoelectromechanical resonators via electrostatic gating article pdf available in micromachines 96. Since its discovery in 2004, graphene has attracted tremendous research e ort worldwide. Capacitive spring softening in singlewalled carbon nanotube nanoelectromechanical resonators chung chiang wu and zhaohui zhong department of electrical engineering and computer science, university of michigan, ann arbor, michigan 48109, united states bs supporting information b ecause of their low mass density and high youngs modu. Highfrequency electromechanical resonators based on thin.
Conclusion a theoretical analysis of nanoelectromechanical oscillators using twodimensional crystal resonators as a frequency determining element has been presented. Dissipation of energy in micro and nano electromechanical resonators governs their dynamical response and limits their potential use in device applications. We measure the quality factor q of electrically driven fewlayer graphene drumhead resonators, providing an experimental demonstration that q. The prototype device demonstrates the feasibility of using multilayer graphene in electromechanical. Chen, graphene nanoelectromechanical resonators and oscillators.
We develop a model that includes intermodal coupling and tensioned graphene resonators. In the first parts of the thesis, i will discuss the. Nonlinear damping in mechanical resonators made from carbon nanotubes and graphene a. Nems form the next logical miniaturization step from socalled microelectromechanical systems, or mems devices. Pdf graphene resonators with high quality factor using a. Graphene, a single atomic layer from graphite 1, is an ideal candidate for nanoelectromechanical applications due to its large youngs modulus and low density. Based on a continuum mechanical model for singlelayer graphene we propose and analyze a microscopic mechanism for dissipation in nanoelectromechanical graphene resonators. Nonlinear dynamics of nanomechanical resonators ron lifshitz and m. Graphene nanoelectromechanical systems as stochastic. Frequency tuning of graphene nanoelectromechanical.
Electromechanical resonances in suspended bilayer graphene. We describe a chemical sensor technology based on resonant nanoelectromechanical systems nems mass detectors that provides the speed, sensitivity, specificity, and size required by the microscale gc paradigm. Miniaturized gas chromatography gc systems can provide fast, quantitative analysis of chemical vapors in an ultrasmall package. Heinz2,3 and james hone1 the enormous stiffness and low density of graphene make it an ideal material for nanoelectromechanical applications. This is a promising approach with graphene resonators, because the twodimensional shape of graphene is ideal for large capacitive coupling. In the first parts of the thesis, i will discuss the fabrications and measurements of typical graphene nems resonators, including doubly clamped and fully clamped graphene mechanical resonators. Request pdf graphene nanoelectromechanical systems as stochasticfrequency oscillators we measure the quality factor q of electricallydriven fewlayer graphene drumhead resonators, providing. Polymerfree, low tension graphene mechanical resonators.
The devices exhibit onoff ratios of up to 104 and lifetimes of over 500 cycles. The structures could be used to make nanoelectromechanical systems nems for a variety of sensing, signal processing and communications applications that would. Studies of graphenebased nanoelectromechanical switches. Schematics of grapheneresonator are composed of a suspended grapheneribbon placed on the bottom gate with spacing and clamps on both ends, as shown in fig. Nanoelectromechanical silicon carbide resonators for ultra. Pdf oscillators, which produce continuous periodic signals from direct current power. The optimum clock source type for a particular application is dependent on factors including cost, accuracy and environmental parameters. We also find that doubly clamped graphene resonators can have a wider. Graphene based nanoelectromechanical systems nems working in radio frequency rf regime possess considerable advantages own to the remarkable electrical and mechanical properties of this atomic. Nems typically integrate transistorlike nanoelectronics with mechanical actuators, pumps, or motors, and may thereby form physical. Capacitive spring softening in singlewalled carbon. Researchers show that grapheneelectrode based piezoelectric nems resonators operate at their theoretical unloaded. Pdf frequency tuning of graphene nanoelectromechanical.
In this study, analysis of the vibration modes of nems resonators using simply supported circular dlgss has been undertaken based on nonlocal thin plate theory. Nonlocal vibration analysis of nanomechanical systems. Mechanisms of linear dissipation in micro and nanomechanical. Probing thermal expansion of graphene and modal dispersion at lowtemperature using graphene nanoelectromechanical systems resonators. Crystals, ceramic resonators, rc oscillators and silicon oscillators are four types of clock source suited for use with microcontrollers. Highfrequency electromechanical resonators based on thin gate. Guaranteed by the superior electrical and excellent mechanical properties, graphene is the ideal building block for nanoelectromechanical systems nems. An outstanding challenge, however, has been to obtain large coupling between the motion and external systems for efficient readout and manipulation. Made of only one sheet of carbon atoms, graphene is the thinnest yet strongest material ever exist. In this article, we report on a comprehensive modeling study of frequency tuning of graphene resonant nanoelectromechanical systems. Graphene opens up new applications for microscale resonators operation at high temperatures and broad tunability could bring microelectromechanical resonators to space and beyond by dexter johnson.
Graphene is an attractive material for nanomechanical devices because it allows for exceptional properties, such as high frequencies, quality factors, and low mass. Graphene nanoelectromechanical resonators and oscillators changyao chen made of only one sheet of carbon atoms, graphene is the thinnest yet strongest material ever exist. These results indicate that graphene nanoribbons can serve as allelectronic ultrahigh frequency oscillators and. Development of nanoelectromechanical resonators for rfic. Molecular dynamics modeling and simulation of a graphene. Nanoelectromechanical resonator arrays for ultrafast, gasphase chromatographic chemical analysis. The model applies to both doubly clamped graphene membranes and circumferenceclamped circular drumhead device structures. In this article, we report on a comprehensive modeling study of frequency tuning of graphene resonant nanoelectromechanical systems nems via electrostatic coupling forces induced by controlling the voltage of a capacitive gate. Experimental characterization of graphene by electrostatic. Since its discovery in 2004, graphene has attracted tremendous research effort worldwide. Graphene mechanical oscillators with tunable frequency.
This poor repeatability makes it impossible to use these resonators to make accurate, highprecision force and displacement sensors or electromechanical filters. Their on and off states can be controlled by modulating the electrostatic force applied to the graphene. In the last decade, graphene membranes have drawn tremendous. Nonlinear dissipation in diamond nanoelectromechanical. The enormous stiffness and low density of graphene make it an ideal material for nanoelectromechanical applications. The effect of strain on the resonant frequency of a graphene stretched circular plate has been analyzed. For nem resonators in general, several processes leading to linear damping ld have been investigated. Mceuen1 nanoelectromechanical systems were fabricated from single. S1, for more detail for the selfsustaining oscillator, which includes the frequencydetermining uhf nems resonator and the. Here, we demonstrate the fabrication and electrical readout of. Because the resonators are atomically thin, outofplane fluctuations are large.
Here, we employ a di erent strategy, which is to couple the mechanical resonator capacitively to a superconducting cavity 12, 2428. Bolotin3, william kalb1,philipkim3, ioannis kymissis2, horstl. A nanotube under tensile stress, a nanotube with slack, and a graphene sheet under tensile stress. Fewlayer graphene resonator device image and nanomechanical resonance data. The simplest model of a doubly clamped graphene membrane resonator is as a sheet under tension1,2,4,5,7 where yt 340 nm and f 0 7.
Here, we report on a novel approach, in which we capacitively couple a highq. Nanoelectromechanical systems nems are a class of devices integrating electrical and mechanical functionality on the nanoscale. In particular, graphene resonators 3,1118, are known to display strong geometric nonlinear conservative as well as nonlinear dissipative response 2,14,1921. Introduction the recent isolation of graphene 1, a twodimensional. Tunable graphene based nanoelectromechanical resonators. Tanenbaum d m, parpia j m, craighead h g and mceuen p l 2007 electromechanical resonators from graphene sheets science 315 4903. In this letter, we show that graphenebased nanoelectromechanical devices are extremely well suited for. Graphene resonators can stand the heat physics world. Yang condensed matter physics, california institute of technology pasadena, california 91125 c. Frequency tuning of graphene nanoelectromechanical resonators. Feng 2, id 1 school of electronic science and engineering, university of electronic science and technology of china, chengdu 611731, china. Mehregany electrical engineering and computer science case western reserve u.
Nanoelectromechanical resonator arrays for ultrafast, gas. We have developed a micromanipulation technique to fabricate mechanical resonators 2, 3 out of suspended graphene. Doublelayer graphene sheets dlgss have potential applications as nanoelectromechanical systems nems resonators due to their specific carrier spectrum of electrons. Single and fewlayer graphene resonators have been fabricated with the recently. Yang r, wang z, ye g j, chen x h, shan j and feng p x l 2015 black phosphorus nanoelectromechanical resonators vibrating at very high. Development of nanoelectromechanical resonators for rfic applications william d. In classical continuum theory, the resonance frequencies f of strings are basically tuned by the tension t in such a way that f. The combination of highfrequency vibrations and metallic transport in graphene makes it a unique material for nanoelectromechanical devices. We nd that coupling between exural modes and inplane phonons leads to. Performance of monolayer graphene nanomechanical resonators with electrical readout changyao chen1, sami rosenblatt2, kirill i. Frequency tuning, nonlinearities and mode coupling in. Coupling graphene mechanical resonators to superconducting. Electromechanical resonators from graphene sheets j. This has meant that graphenebased nanoelectromechanical resonators tend to have large variations in natural frequency and quality factor from device to device.
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