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Updated: May 30, 2026
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Published on: August 22, 2017
Extended acoustic modes in random systems with n-mer short range correlations
D F Barros1, A E B Costa, F A B F de Moura
1Instituto de Física, Universidade Federal de Alagoas, Maceió-AL 57072-970, Brazil.
Summary
This study explores acoustic wave propagation in a 1D medium with correlated elasticity. The research reveals that only specific resonant frequencies are transmitted, while others decay, offering insights into wave behavior in disordered systems.
Area of Science:
- Condensed matter physics
- Acoustics
- Wave propagation
Background:
- Studying wave propagation in disordered media is crucial for understanding material properties.
- Previous models like the random-dimer model provide a basis for exploring local correlations.
Purpose of the Study:
- To investigate acoustic wave propagation in a 1D medium with short-range correlated elasticity.
- To analyze the impact of a disordered binary distribution with finite segments on wave transmission.
Main Methods:
- Analytical procedures to identify system resonances.
- Numerical transfer matrix formalism.
- Second-order finite-difference method for detailed wave analysis.
Main Results:
- The system exhibits n-1 resonances with specific frequencies (ω(r)).
- Acoustic modes not matching these resonant frequencies decay.
- The medium selectively transmits only the resonant frequencies ω(r).
Conclusions:
- The correlated elasticity distribution leads to frequency-selective transmission of acoustic waves.
- This model generalizes the random-dimer model, offering new insights into wave phenomena in disordered materials.
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