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Eichenfield, Matt

Publications and source records attributed to Eichenfield, Matt.

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Microsystems-based method and apparatus for passive detection and processing of radio-frequency signals

A radio frequency (RF) receiver comprises a passive impedance transforming voltage amplifier and a resonant, latching micromechanical switch having a deflectable bridge, an RF actuation electrode receivingly connected to the amplifier, and a DC bias electrode positioned to latch the switch in a closed position by electrostatic attraction when energized by a suitable voltage. The bridge is configured with a mechanical mode of vibration that periodically urges the switch toward the closed position.

47 OTHER INSTRUMENTATION↗
DOE OSTI2018

Vertically integrated optoelectronics package for MEMS devices

The present application relates to vertically integrated assemblies including a MEMS-based optomechanical architecture. In some embodiments, the assembly includes a MEMS/optoelectronic module, an emitter module, and a detector module, where these modules are vertically integrated. Methods of fabricating such assemblies are also described herein.

42 ENGINEERING↗
DOE OSTI2018

Investigation of a Solid-State Tuning Behavior in Lithium Niobate

Electric field-based frequency tuning of acoustic resonators at the material level provides an enabling technology for building complex tunable filters. Tunable acoustic resonators were fabricated in thin plates (h/λ ~ 0.05) of X-cut lithium niobate (90°, 90°, ψ = 170°). Lithium niobate is known for its large electromechanical coupling (SH: K 2 40%) and thus applicability for low-insertion loss and wideband filter applications. We demonstrate the effect of a DC bias to shift the resonant frequency by ~0.4% by directly tuning the resonator material. The mechanism is based on the nonlinearities that exist in the piezoelectric properties of lithium niobate. Devices centered at 332 MHz achieved frequency tuning of 12 kHz/V through application of a DC bias.

47 OTHER INSTRUMENTATION↗
DOE OSTI2018

Lamb Wave Focusing Transducer for Efficient Coupling to Wavelength-Scale Structures in Thin Piezoelectric Films

This study describes the theoretical and experimental investigation of interdigitated transducers (IDTs) capable of producing focused acoustical beams in thin film piezo-electric materials. A mathematical formalism describing focused acoustical beams, Lamb beams, is presented and related to their optical counterparts in two- and three-dimensions. A novel Fourier domain transducer design methodology was developed and utilized to produce near diffraction limited focused beams with in a thin film AlN membrane. The properties of the acoustic beam formed by the transducer were studied by means of Doppler vibrometry implemented with a scanning confocal balanced homodyne interferometer. Fourier domain modal analysis confirmed that 85% of the acoustical power was delivered to the targeted focused beam which was constituted from the lowest order symmetric mode, while 2% was delivered unintentionally to the beam formed from the anti-symmetric mode, and the remaining power was isotropically scattered. The transmission properties of the acoustic beams as they interact with devices with wavelength scale features were also studied, demonstrating minimal insertion loss for devices in which a subwavelength, pinhole apertures was included.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

Optomechanical force sensors, cantilevers, and systems thereof

An optomechanical force sensor includes a substrate, a cantilevered beam anchored to the substrate, and a probe tip positioned near an end of the cantilevered beam distal to the substrate. A suspended waveguide is disposed on the cantilevered beam and is optically continuous with an input/output waveguiding structure. An optical cavity is defined within the suspended waveguide.

42 ENGINEERING↗
DOE OSTI2018

Second harmonic generation in resonant optical structures

An optical second-harmonic generator (or spontaneous parametric down-converter) includes a microresonator formed of a nonlinear optical medium. The microresonator supports at least two modes that can be phase matched at different frequencies so that light can be converted between them: A first resonant mode having substantially radial polarization and a second resonant mode having substantially vertical polarization. The first and second modes have the same radial order. The thickness of the nonlinear medium is less than one-half the pump wavelength within the medium.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Reduced Dimensionality Lithium Niobate Microsystems

The following report describes work performed under the LDRD program at Sandia National Laboratories October 2014 and September 2016. The work presented demonstrates the ability of Sandia Labs to develop state-of-the-art photonic devices based on thin film lithium niobate (LiNbO 3 ). Section 1 provides an introduction to integrated LiNbO 3 devices and motivation for developing thin film nonlinear optical systems. Section 2 describes the design, fabrication, and photonic performance of thin film optical microdisks fabricated from bulk LiNbO 3 using a bulk implantation method developed at Sandia. Sections 3 and 4 describe the development of similar thin film LiNbO 3 structures fabricated from LiNbO 3 on insulator (LNOI) substrates and our demonstration of optical frequency conversion with state-of-the-art efficiency. Finally, Section 5 describes similar microdisk resonators fabricated from LNOI wafers with a buried metal layer, in which we demonstrate electro-optic modulation.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Piezoelectric Nano-Optomechanical Systems

Lithium niobate, due to its material properties, is often used for optical waveguides, optical modulators, and other linear and nonlinear optical applications. In this research, we present monolithically integrated microdisk resonators with an integrated ground plane fabricated from a commercially purchased lithium niobate on insulator wafer. Using this architecture, we demonstrate excitation of a 167MHz mechanical resonance as well as electro-optic modulation of a 1.93THz optical mode in a free-standing whispering gallery mode (WGM) resonator. By hovering a signal probe above the disk while grounding the device using the integrated ground plane, an electric field can be applied across the device which both induces an electro-optic effect as well as drives mechanical motion via the piezoelectric effect. Detection of the mechanical mode and electro-optic shift was performed by coupling to the high quality factor (Q = 454,000) optical modes of the microresonator using a tapered optical fiber.

42 ENGINEERING↗