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Abstract A coupled resonant acoustic waveguide (CRAW) in a phononic crystal (PnC) was engineered to manipulate the propagation of ultrasonic waves within a conventional phononic bandgap for wavelength division multiplexing. The PnC device included two, forked, distinct CRAW waveguide channels that exhibited strong frequency and mode selectivity. Each branch was composed of cavities of differing volumes, with each giving rise to deep and shallow ‘impurity’ states. These states were utilized to select frequency windows where transmission along the channels was suppressed distinctly for each channel. Though completely a linear system, the mode sensitivity of each CRAW waveguide channel produced apparent nonlinear power dependence along each branch. Nonlinearity in the system arises from the combination of the mode sensitivity of each CRAW channel and small variations in the shape of the incident wavefront as a function of input power. The all-acoustic effect was then leveraged to realize an ultrasonic, spatial signal modulator, and logic element operating at 398 and 450 kHz using input power.
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Acoustic waveguide demultiplexer based on Fano resonance: Experiment and simulation
A compact acoustic waveguide demultiplexer configuration is studied via finite-element numerical modeling and audio frequency experiments. The demultiplexer consists of a Y-shaped waveguide with a single input and two outputs. The narrow transmission bands created by stubs side-loaded on each output arm lead to selective transmission of certain frequencies. The experimental work characterizes the broadband response along each output arm by using an impulse response method. Finite-element numerical simulations are conducted using COMSOL. The results of the experiment and the simulation are compared to an existing analytic theory.
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- Award ID(s):
- 1757493
- PAR ID:
- 10597422
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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