3 edition of On spurious bulk wave excitation in SAW grating reflectors on GaAs(001)(110) found in the catalog.
On spurious bulk wave excitation in SAW grating reflectors on GaAs(001)(110)
by National Aeronautics and Space Administration, National Technical Information Service, distributor in [Washington, DC, Springfield, Va
Written in English
|Statement||E. Danicki and W.D. Hunt.|
|Series||[NASA contractor report] -- NASA-CR-201107., NASA contractor report -- NASA CR-201107.|
|Contributions||Hunt, W. D., United States. National Aeronautics and Space Administration.|
|The Physical Object|
Surface Acoustic Wave Devices in Telecommunications: Modelling and Simulation Professor Ken-ya Hashimoto (auth.) Although the existence of the surface acoustic wave (SAW) was first dis cussed in by Lord Rayleigh , it did not receive engineering interest for a long time. The frequency response of such SAW filters are governed by configurations of IDT’s and grating reflectors fabricated on piezoelectric substrates. This is a first order model that does not take into account any second order effects such as reflections, spurious bulk acoustic wave (BAW) generation, wave diffraction, beam steering due to.
Broadband high reflectivity in subwavelength-grating slab waveguides Xuan Cui,1 1Hao Tian, and Zhongxiang Zhou,1, * 1 Department of Physics, Harbin Institute of Technology, Harbin , China Abstract: We computationally study a subwavelength dielectric grating structure, show that slab waveguide modes can be used to obtain broadband. Surface Acoustic Wave (SAW) sensor technology for harsh environments aimed at aerospace applications. To aid in development of sensors a model of a SAW strain sensor has been developed. The new model extends the modified matrix method to include the response of Orthogonal Frequency Coded (OFC) reflectors and the response of SAW devices to strain.
In a representative embodiment, a bulk acoustic wave (BAW) resonator, comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode, the first piezoelectric layer having a first c-axis oriented along a first direction; a second electrode disposed over the first piezoelectric layer; and a second piezoelectric layer disposed over the first. A new wireless and passive surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound (OC) detection is presented. A MHz reflective delay line configuration composed by single phase unidirectional transducers (SPUDTs) and three shorted reflectors was fabricated on YZ LiNbO3 piezoelectric substrate as the sensor element.
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Dr. Hunt grew up in the literary haven of Columbus, Mississippi, the boyhood home of Tennessee Williams, and received his B.S.E.E. from the University of Alabama in He worked for Harris Corporation for two years in the areas of acousto-optics and surface acoustic wave (SAW). He then entered the Massachusetts Institute of Technology where he earned his S.M.E.E.
in Get this from a library. On spurious bulk wave excitation in SAW grating reflectors on GaAs()(). [E Danicki; W D Hunt; United States. National Aeronautics and Space Administration.].
On spurious bulk wave excitation in SAW grating reflectors on GaAs()() By E. Danicki and W. Hunt. Abstract. Reflection of SAW (surface acoustic waves) from groove gratings on a cubic crystal is analyzed numerically on the basis of perturbation theory.
It is shown that for certain angles of incidence, the conversion of SAW into bulk Author: E. Danicki and W. Hunt. Danickiand W. Hunt, “ On spurious bulk wave excitation in SAW grating reflectors on GaAs ()(),” Arch. Acoust. 20, – (). Google ScholarCited by: Abstract: This paper proposes a technique to analyze surface acoustic wave (SAW) scattering at discontinuity in grating structures using the hierarchical cascading technique.
The traveling wave excitation is applied to generate a specific SAW mode. Then the displacement distribution is obtained for the passive by: 1. The reflection and bulk‐wave loss characteristics of a SAW reflector grating comprised of shallow grooves are treated using the coupled‐mode approach well known in the area of optical gratings.
This approach offers the following distinct advantages over the previously reported equivalent network approach: (i) it derives the grating characteristics directly in terms of the material.
The SAW technology allows us to arrange the location of multiple resonances by the proper design of the electrode pattern.
6) RF BAW devices, such as film bulk acoustic wave resonators (FBARs) 2. In this paper, we study supersonic surface acoustic wave modes in shallow hole phononic crystals computationally with respect to the three bulk wave sound barriers of cubic () GaAs.
Surface acoustic waves in two-dimensional phononic crystals consisting of a square array of shallow, two to three micron deep cylindrical void inclusions are studied computationally via the finite.
This paper proposes a method of deriving the discrete Green function for the analysis of surface acoustic wave (SAW) propagation and excitation under metallic-grating structures with finite thickness.
Interaction between the Rayleigh-type SAW and the SH-wave in a periodic grating on a °LN substrate Surface acoustic wave devices in.
Abstract: In planar bulk acoustic wave devices, an interdigital transducer (IDT) is generally used as the source of excitation.
Grooves, which convert an incident SAW (surface acoustic wave) to bulk waves and vice versa, also have the potential to be used as an alternative (if secondary) source of excitation. This chapter aims to give the basics of surface acoustic wave (SAW) devices.
First, the basic operation of interdigital transducers (IDTs) is discussed. The delta-function model is introduced, and the coupling-of-modes theory is adopted to allow for the influence of SAW reflection in the analysis.
Next, SAW transversal filters are discussed. A surface acoustic wave (SAW) is most conveniently excited on a piezoelectric crystal using an interdigitated electrode pattern, or interdigital transducer (IDT), as shown in Figure (page 75). Application of a voltage between alternately connected electrodes causes a periodic electric field to be imposed on the crystal.
Strong Wave Confinementa, ma, oto, and chi, “Suppression of Transverse Mode Responses in Ultra-Wideband SAW Resonators Fabricated on a Cu-grating/15 o YX-LiNbO. Figure 14 shows an example spectral reflectance, calculated by RCWA, of a one-dimensional subwavelength antireflection grating formed by etching a GaAs substrate.
The resulting reflectance (below ∼% at the center wavelength of μm) with the grating layer is much lower than the bulk GaAs substrate reflection (∼28%). The wave vector of the diffracted output beam is the vector sum of the input wave vector and the acoustical wave vector; out-of-band frequencies remain undeviated.
Crystals such as TeO 2, quartz, and MgF 2 are highly transmitting and have an efficient acousto-optic response in different wavelength regimes from nm to 5 μm. Applying an alternating current (AC) or radio frequency (RF) excitation to electrodes patterned on a piezoelectric material generates an acoustic wave that propagates in the direction perpendicular to the surface of the material into the bulk medium (bulk acoustic wave, BAW) or along the surface of the material (surface acoustic wave, SAW).
grating Prior art date Application number PCT/US/ Other languages French (fr) Inventor Gianluca Piazza Christian CASSELLA Original Assignee Carnegie Mellon University Priority date (The priority date is an assumption and is not a legal conclusion.
This is demonstrated in the text by the presentation of fundamental principles before the introduction of advanced/special topics A history of surface acoustic wave devices, D.P.
Morgan; thin films for SAW devices, F.S. Hickemell; bulk and surface acoustic waves in anisotropic solids, E.L. Adler; analysis of SAW excitation and propagation under.
Therefore, while conventional “bulk” wave UT systems can generally only inspect an area very close to or directly beneath the transducer, guided wave systems can detect flaws many feet away from the transducer, and in some cases several hundred feet away. Due to the unique properties of guided waves, they are also capable of detecting small.It is instructive to consider the spatial frequencies of the position-dependent phase changes caused by a grating.
In the simplest case of a sinusoidal phase variation, there are only two non-vanishing spatial frequency components with ±2 π / d, where d is the period of the grating structure.
An incident beam with an angle θ against the normal direction has a wave vector component k sin.Surface-Acoustic-Wave Resonators, by Peter S. Cross and Scott S.
Elliott By reflecting This advance in SAW excitation initiated a new wave of interest in SAW devices to capitalize on their novel proper Frequency response of a MHz SAW delay line. By adding grating reflectors at each end, a resonant peak is obtained at the center.