【摘 要】
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The acoustic wave band structures and single defect states of the two-dimensional periodic composite media ofwater (mercury) cylinders with circular cross secti
【机 构】
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Department of Applied Physics, South China University of Technology, Guangzhou 510641“,”Department o
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The acoustic wave band structures and single defect states of the two-dimensional periodic composite media ofwater (mercury) cylinders with circular cross section in mercury (water) host was studied by using the planewaves method and supercell calculations. We find that the numbers of gaps in the first 50 bands versus the fillingfraction have similar results as gap/midgap ratio of the lowest gap in the period systems. Only one band gapexhibits in the wide range of filling fraction, and several defect states are created inside the band gaps in singledefect systems. The influences of the filling fraction and defect radius on the band structure are investigated.
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