Active feedback is used with two electrodes of a four-electrode capacitive-gap transduced wine-glass disk resonator to enable boosting of an intrinsic resonator Q and to allow independent control of insertion loss across the two other electrodes. Two such Q-boosted resonators configured as parallel micromechanical filters may achieve a tiny 0.001% bandwidth passband centered around 61 MHz with only 2.7 dB of insertion loss, boosting the intrinsic resonator Q from 57,000, to an active Q of 670,000. The split capacitive coupling electrode design removes amplifier feedback from the signal path, allowing independent control of input-output coupling, Q, and frequency. Controllable resonator Q allows creation of narrow channel-select filters with insertion losses lower than otherwise achievable, and allows maximizing the dynamic range of a communication front-end without the need for a variable gain low noise amplifier.

A micro-electromechanical system (MEMS) frequency divider apparatus having one or more MEMS resonators on a substrate is presented. A first oscillator frequency, as an approximate multiple of the parametric oscillation frequency, is capacitively coupled from a very closely-spaced electrode (e.g., 40 nm) to a resonant structure of the first oscillator, thus inducing mechanical oscillation. This mechanical oscillation can be coupled through additional MEMS resonators on the substrate. The mechanical resonance is then converted, in at least one of the MEMS resonators, by capacitive coupling back to an electrical signal which is a division of the first oscillation frequency. Output may be generated as a single ended output, or in response to a differential signal between two output electrodes.

Embodiments of the invention include micromechanical resonators. These resonators can be fabricated from thin silicon layers. Both rotational and translational resonators are disclosed. Translational resonators can include two plates coupled by two resonate beams. A stable DC bias current can be applied across the two beams that causes the plates to resonate. In other embodiments, disk resonators can be used in a rotational mode. Other embodiments of the invention include using resonators as timing references, frequency sources, particle mass sensors, etc.

The present description concerns a clock signal generation device (902) comprising: a microelectromechanical resonant element (504); and at least one nanoelectromechanical transduction element (512).

System and methods for a hollow-disk radial-contour mode resonator structure. The hollow disk reduces the dynamic mass and stiffness of the structure. Since electromechanical coupling C.sub.x/C.sub.o goes as the reciprocal of mass and stiffness, the hollow disk structure has a considerably stronger electromechanical coupling than a solid one at the same frequency, and thus raises C.sub.x/C.sub.o without excessive gap-scaling. Several embodiments of hollow disk resonators are detailed, including asymmetric and symmetric disk configurations.

A resonator element of the monocrystalline 4H or 6H polytype of silicon carbide. A MEMS device including the resonator element and a substrate, wherein the resonator element and the substrate are not coplanar, and acoustic decoupling of the resonator element and the substrate is at least partially dependent upon a degree to which the resonator element and the substrate are not coplanar. A MEMS gyroscope including the resonator element, a substrate, one or more electrodes disposed proximate the resonator element, and a capacitive gap disposed between each electrode and the resonator element. A MEMS device including the resonator element having has a Q greater than 1,000,000, a phononic crystal substrate, and a gap disposed between a perimeter edge of the resonator element and the phononic crystal substrate, wherein acoustic decoupling of the resonator element and the phononic crystal substrate is at least partially dependent upon a size of the gap.

The technology described herein is directed towards a reconfigurable intelligent surface (RIS) based on bimorph microelectromechanical systems (MEMS) technology, in which bimorph MEMS micro-actuators are integrated into unit cells of the RIS. A ring-shaped bimorph cantilever, resulting from unit cell fabrication, operates as an electrothermal actuator in the unit cell's resonating pattern. A controlled voltage is applied to the ring-shaped bimorph cantilever, deforming (bending down) the bimorph ring at its non-anchored (free) portion from its upwardly curved non-actuated state via joule heating. The amount of vertical displacement of the free portion of the bimorph ring when voltage is applied changes the structure of the unit cell's geometry based on the amount of voltage, whereby analog-like tuning of the unit cell's characteristics (including phase shift) is obtained. When combined with the voltage-controlled phase shifts of other unit cells of the RIS, beamforming of a reflected incoming electromagnetic wave is facilitated.