Abstract: An optical detector for detecting radio frequency (RF) signals, the optical detector comprising a light source and a photodetector, and an electrical circuit comprising a position dependent capacitor and a bias voltage source adapted for providing a bias voltage for biasing the position dependent capacitor, the position dependent capacitor comprising an electrode and a membrane being displaceable in reaction to RF signals incident on the membrane, the membrane being metallized, has a thickness of less than 1 ?m and a quality factor, Qm, of at least 20,000, and the distance between the membrane and the electrode being less than 10 ?m.

Abstract: Synchronization of oscillators based on anharmonic nanoelectromechanical resonators. Experimental implimentation allows for unprecedented observation and control of parameters governing the dynamics of synchronization. Close quantitative agreement is found between experimental data and theory describing reactively coupled Duffing resonators with fully saturated feedback gain. In the synchonized state, a significant reduction in the phase noise of the oscillators is demonstrated, which is key for applications such as sensors and clocks. Oscillator networks constructed from nanomechanical resonators form an important laboratory to commercialize and study synchronization—given their high-quality factors, small footprint, and ease of co-integration with modern electronic signal processing technologies. Networks can be made including one-, two-, and three-dimensional networks. Triangular and square lattices can be made.

Abstract: A passive electro-mechanical device that reduces phase noise in oscillators, thereby improving their frequency precision. The noise reduction device can consist of a pair of coupled nonlinear resonators that are driven parametrically—by modulating their natural frequency in time, through the output signal of a conventional oscillator at a frequency close to the sum of the linear mode frequencies. Above the threshold for parametric response, the coupled resonators can exhibit oscillation at an inherent frequency. The novel possibility for noise elimination is realized by tuning the system to operating points for which this periodic signal is immune to frequency noise in the drive signal, providing a way to clean the phase noise of the driving oscillator.

Abstract: An optical detector for detecting radio frequency (RF) signals, the optical detector comprising a light source and a photodetector, and an electrical circuit comprising a position dependent capacitor and a bias voltage source adapted for providing a bias voltage for biasing the position dependent capacitor, the position dependent capacitor comprising an electrode and a membrane being displaceable in reaction to RF signals incident on the membrane, the membrane being metallized, has a thickness of less than 1 ?m and a quality factor, Qm, of at least 20,000, and the distance between the membrane and the electrode being less than 10 ?m.

Abstract: A passive electro-mechanical device that reduces phase noise in oscillators, thereby improving their frequency precision. The noise reduction device can consist of a pair of coupled nonlinear resonators that are driven parametrically—by modulating their natural frequency in time, through the output signal of a conventional oscillator at a frequency close to the sum of the linear mode frequencies. Above the threshold for parametric response, the coupled resonators can exhibit oscillation at an inherent frequency. The novel possibility for noise elimination is realized by tuning the system to operating points for which this periodic signal is immune to frequency noise in the drive signal, providing a way to clean the phase noise of the driving oscillator.

Abstract: Doubly-clamped nanowire electromechanical resonators that can be used to generate parametric oscillations and feedback self-sustained oscillations. The nanowire electromechanical resonators can be made using conventional NEMS and CMOS fabrication methods. In very thin nanowire structures (sub-micron-meter in width), additive piezoresistance patterning and fabrication can be highly difficult and thus need to be avoided. This invention shows that, in piezoresistive nanowires with homogeneous material composition and symmetric structures, no conventional and additive piezoresistance loops are needed. Using AC and DC drive signals, and bias signals of controlled frequency and amplitude, output signals having a variety of frequencies can be obtained. Various examples of such resonators and their theory of operation are described.

Abstract: Synchronization of oscillators based on anharmonic nanoelectromechanical resonators. Experimental implimentation allows for unprecedented observation and control of parameters governing the dynamics of synchronization. Close quantitative agreement is found between experimental data and theory describing reactively coupled Duffing resonators with fully saturated feedback gain. In the synchonized state, a significant reduction in the phase noise of the oscillators is demonstrated, which is key for applications such as sensors and clocks. Oscillator networks constructed from nanomechanical resonators form an important laboratory to commercialize and study synchronization—given their high-quality factors, small footprint, and ease of co-integration with modern electronic signal processing technologies. Networks can be made including one-, two-, and three-dimensional networks. Triangular and square lattices can be made.

Abstract: Doubly-clamped nanowire electromechanical resonators that can be used to generate parametric oscillations and feedback self-sustained oscillations. The nanowire electromechanical resonators can be made using conventional NEMS and CMOS fabrication methods. In very thin nanowire structures (sub-micron-meter in width), additive piezoresistance patterning and fabrication can be highly difficult and thus need to be avoided. This invention shows that, in piezoresistive nanowires with homogeneous material composition and symmetric structures, no conventional and additive piezoresistance loops are needed. Using AC and DC drive signals, and bias signals of controlled frequency and amplitude, output signals having a variety of frequencies can be obtained. Various examples of such resonators and their theory of operation are described.

Abstract: A parametric feedback oscillator includes a resonator which has at least one transduction element and at least one electromechanical resonating element. The resonator is configured to accept as input a parametric excitation signal at a frequency 2?0 and to provide a resonating output signal at a frequency ?0. A cascaded feedback path in any electrically coupled cascade order includes at least one non-linear element, at least one phase shifter electrically, and at least one amplifier. The cascade feedback path is configured to receive as input the resonating output signal at a frequency ?0 and configured to provide as output a feedback path signal as the parametric excitation signal at a frequency 2?0 to the resonator. A parametric feedback oscillator output terminal is configured to provide the resonating output signal at the frequency ?0 as an output signal. A method of causing a parametric feedback oscillation is also described.

Abstract: A parametric feedback oscillator includes a resonator which has at least one transduction element and at least one electromechanical resonating element. The resonator is configured to accept as input a parametric excitation signal at a frequency 2?0 and to provide a resonating output signal at a frequency ?0. A cascaded feedback path in any electrically coupled cascade order includes at least one non-linear element, at least one phase shifter electrically, and at least one amplifier. The cascade feedback path is configured to receive as input the resonating output signal at a frequency ?0 and configured to provide as output a feedback path signal as the parametric excitation signal at a frequency 2?0 to the resonator. A parametric feedback oscillator output terminal is configured to provide the resonating output signal at the frequency ?0 as an output signal. A method of causing a parametric feedback oscillation is also described.