由於聲學超材料特殊的負質量密度與負體積模數特性，不少學者投入了該領域的探索與應用。為了使聲波超材料發揮更佳的阻絕聲波傳遞特性，本文先利用離散模型去分析質量體由不同排列方式所組成的單位結構系統，歸納出質量體排列方式對系統特性的影響，接著再根據其特性，提出兩種排列方式較複雜的複合型內質量結構，並證明其比排列方式較單純的單位結構擁有更佳的阻絕聲波特性。最後再將此概念發展至連體系統，並以有限元素軟體分析複合型內質量結構之運動模態與帶隙特性，得知本文提出的模型，實際應用中可以有效地阻絕特定頻率範圍內的聲波傳遞。

Acoustic metamaterial has the ability to achieve unusual properties of negative mass density and negative bulk modulus. In last years many researchers have started to examine the possibility of designing materials with negative refractive index. In this work, we propose geometric arrangements of discrete mass systems to demonstrate the band structure of various periodic lattice. To improve the sound insulation property, it is desirable to increase the number of band gaps and its band width. We thus propose two discrete multimode mass-in-mass lattice systems that are constructed by two kinds of complex masses arrangement. We show that the band gap structures of these systems are better than the simple arranged discrete multimode mass-in-mass lattice systems. Lastly, we extend the concept to a continuum system using a finite element simulation. The result shows that our proposed systems are indeed feasible.

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