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Title: Dynamical effective parameters of elastic superlattice with strong acoustic contrast between the constituents
Analytical formulas are obtained for frequency-dependent effective elastic modulus and effective mass density for a periodic layered structure. The proposed homogenization procedure is valid at sufficiently high frequencies well above the lowest band gap in the acoustic spectrum of the structure. It is shown that frequency-dependent effective parameters may take negative values either in different regions of frequencies or in the same quite narrow region. This property demonstrates that 1D elastic structure may behave in the limit of small Bloch wave vectors as a double-negative acoustic metamaterial.  more » « less
Award ID(s):
1741677
PAR ID:
10078554
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of low temperature physics
Volume:
44
Issue:
12
ISSN:
0022-2291
Page Range / eLocation ID:
1639-1644
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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