Plane Wave-Perturbative Method for Evaluating the Effective Speed of Sound in 1D Phononic Crystals

<div>Effective sound velocity for longitudinal vibrational modes propagating along the growth direction of a W-Al superlattice. Here, solid line was obtained by using formula (<a href="https://static.hindawi.com/articles/amse/volume-2016/3017835/figures/#EEq34">33</a>) and squares were obtained by using formula (<a href="https://static.hindawi.com/articles/amse/volume-2016/3017835/figures/#EEq37">36</a>).</div>

Advances in Materials Science and Engineering

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Figure 6

Figure 6: Plane Wave-Perturbative Method for Evaluating the Effective Speed of Sound in 1D Phononic Crystals 