7 research outputs found
Micromechanical resonator driven by radiation pressure force
Radiation pressure exerted by light on any surface is the pressure generated by the momentum of impinging photons. The associated force - fundamentally, a quantum mechanical aspect of light - is usually too small to be useful, except in large-scale problems in astronomy and astrodynamics. In atomic and molecular optics, radiation pressure can be used to trap or cool atoms and ions. Use of radiation pressure on larger objects such as micromechanical resonators has been so far limited to its coupling to an acoustic mode, sideband cooling, or levitation of microscopic objects. In this Letter, we demonstrate direct actuation of a radio-frequency micromechanical plate-type resonator by the radiation pressure force generated by a standard laser diode at room temperature. Using two independent methods, the magnitude of the resonator's response to forcing by radiation pressure is found to be proportional to the intensity of the incident light.https://www.nature.com/articles/s41598-017-16063-4.epdfPublished versio
Measurement of nonlinear piezoelectric coefficients using a micromechanical resonator
We describe and demonstrate a method by which the nonlinear piezoelectric properties of a piezoelectric material may be measured by detecting the force that it applies on a suspended micromechanical resonator at one of its mechanical resonance frequencies. Resonators are used in countless applications; this method could provide a means for better-characterizing material behaviors within real MEMS devices. Further, special devices can be designed to probe this nonlinear behavior at specific frequencies with enhanced signal sizes. The resonators used for this experiment are actuated using a 1-μm-thick layer of aluminum nitride. When driven at large amplitudes, the piezoelectric layer generates harmonics, which are measurable in the response of the resonator. In this experiment, we measured the second-order piezoelectric coefficient of aluminum nitride to be −(23.1±14.1)×10^−22m/V^2.Published versio
Optical Wireless Information Transfer with Nonlinear Micromechanical Resonators
Wireless transfer of information is the basis of modern communication. It
includes cellular, WiFi, Bluetooth and GPS systems, all of which use
electromagnetic radio waves with frequencies ranging from typically 100 MHz to
a few GHz. However, several long-standing challenges with standard radio-wave
wireless transmission still exist, including keeping secure transmission of
data from potential compromise. Here, we demonstrate wireless information
transfer using a line-of-sight optical architecture with a micromechanical
element. In this fundamentally new approach, a laser beam encoded with
information impinges on a nonlinear micromechanical resonator located a
distance from the laser. The force generated by the radiation pressure of the
laser light on the nonlinear micromechanical resonator produces a sideband
modulation signal, which carries the precise information encoded in the subtle
changes in the radiation pressure. Using this, we demonstrate data and image
transfer with one hundred percent fidelity with a single 96 micron by 270
micron silicon resonator element in an optical frequency band. This mechanical
approach relies only on the momentum of the incident photons and is therefore
able to use any portion of the optical frequency banda band that is 10,000
times wider than the radio frequency band. Our line-of-sight architecture using
highly scalable micromechanical resonators offers new possibilities in wireless
communication. Due to their small size, these resonators can be easily arrayed
while maintaining a small form factor to provide redundancy and parallelism.Comment: 6 pages, 4 figure
Measurement of nonlinear piezoelectric coefficients using a micromechanical resonator
We describe and demonstrate a method by which the nonlinear piezoelectric
properties of a piezoelectric material may be measured by detecting the force
that it applies on a suspended micromechanical resonator at one of its
mechanical resonance frequencies. Resonators are used in countless
applications; this method could provide a means for better-characterizing
material behaviors within real MEMS devices. Further, special devices can be
designed to probe this nonlinear behavior at specific frequencies with enhanced
signal sizes. The resonators used for this experiment are actuated using a
1-m-thick layer of aluminum nitride. When driven at large amplitudes, the
piezoelectric layer generates harmonics, which are measurable in the response
of the resonator. In this experiment, we measured the second-order
piezoelectric coefficient of aluminum nitride to be
.Comment: 5 pages, 3 figures, preprin
Nanomechanical detection of the spin Hall effect
The spin Hall effect creates a spin current in response to a charge current
in a material that has strong spin-orbit coupling. The size of the spin Hall
effect in many materials is disputed, requiring independent measurements of the
effect. We develop a novel mechanical method to measure the size of the spin
Hall effect, relying on the equivalence between spin and angular momentum. The
spin current carries angular momentum, so the flow of angular momentum will
result in a mechanical torque on the material. We determine the size and
geometry of this torque and demonstrate that it can be measured using a
nanomechanical device. Our results show that measurement of the spin Hall
effect in this manner is possible and also opens possibilities for actuating
nanomechanical systems with spin currents.Comment: 5 pages + 2 pages supplementary material, 4 figures tota
Micromechanical microphone using sideband modulation of nonlinear resonators
We report the successful detection of an audio signal via sideband modulation
of a nonlinear piezoelectric micromechanical resonator. The
27096-m resonator was shown to be reliable in audio detection for
sound intensity levels as low as ambient room noise and to have an unamplified
sensitivity of 23.9 V/Pa. Such an approach may be adapted in acoustic
sensors and microphones for consumer electronics or medical equipment such as
hearing aids.Comment: 5 pages, 3 figure