中国物理B ›› 2015, Vol. 24 ›› Issue (4): 46201-046201.doi: 10.1088/1674-1056/24/4/046201

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Negative refractions by triangular lattice sonic crystals in partial band gaps

S. Alagoza, B. B. Alagozb, A. Sahina, S. Nurc   

  1. a Department of Physics, Inonu University, Malatya, Turkey;
    b Department of Electrical and Electronics Engineering, Inonu University, Malatya, Turkey;
    c Vocational School of Health Services, Medical Imaging Techniques, Inonu University, Malatya, Turkey
  • 收稿日期:2014-07-17 修回日期:2014-09-04 出版日期:2015-04-05 发布日期:2015-04-05
  • 基金资助:

    Project supported by the Inonu Universty Scientific Research Projects Coordination Unit (Grant Nos. 2012/29 and 2013/56).

Negative refractions by triangular lattice sonic crystals in partial band gaps

S. Alagoza, B. B. Alagozb, A. Sahina, S. Nurc   

  1. a Department of Physics, Inonu University, Malatya, Turkey;
    b Department of Electrical and Electronics Engineering, Inonu University, Malatya, Turkey;
    c Vocational School of Health Services, Medical Imaging Techniques, Inonu University, Malatya, Turkey
  • Received:2014-07-17 Revised:2014-09-04 Online:2015-04-05 Published:2015-04-05
  • Contact: S. Alagoz E-mail:serkan.alagoz@inonu.edu.tr
  • Supported by:

    Project supported by the Inonu Universty Scientific Research Projects Coordination Unit (Grant Nos. 2012/29 and 2013/56).

摘要:

This study numerically demonstrates the effects of partial band gaps on the negative refraction properties of sonic crystal. The partial band gap appearing at the second band edge leads to the efficient transmissions of scattered wave envelopes in the transverse directions inside triangular lattice sonic crystal, and therefore enhances the refraction property of sonic crystal. Numerical simulation results indicate a diagonal guidance of coupled scattered wave envelopes inside crystal structure at the partial band gap frequencies and then output waves are restored in the vicinity of the output interface of sonic crystal by combining phase coherent scattered waves according to Huygens' principles. This mechanism leads to two operations for wavefront engineering: one is spatial wavefront shifting operation and the other is convex-concave wavefront inversion operation. The effects of this mechanism on the negative refraction and wave focalization are investigated by using the finite difference time domain (FDTD) simulations. This study contributes to a better understanding of negative refraction and wave focusing mechanisms at the band edge frequencies, and shows the applications of the slab corner beam splitting and SC-air multilayer acoustic system.

关键词: sonic crystal, negative refraction, wave focusing, partial band gap

Abstract:

This study numerically demonstrates the effects of partial band gaps on the negative refraction properties of sonic crystal. The partial band gap appearing at the second band edge leads to the efficient transmissions of scattered wave envelopes in the transverse directions inside triangular lattice sonic crystal, and therefore enhances the refraction property of sonic crystal. Numerical simulation results indicate a diagonal guidance of coupled scattered wave envelopes inside crystal structure at the partial band gap frequencies and then output waves are restored in the vicinity of the output interface of sonic crystal by combining phase coherent scattered waves according to Huygens' principles. This mechanism leads to two operations for wavefront engineering: one is spatial wavefront shifting operation and the other is convex-concave wavefront inversion operation. The effects of this mechanism on the negative refraction and wave focalization are investigated by using the finite difference time domain (FDTD) simulations. This study contributes to a better understanding of negative refraction and wave focusing mechanisms at the band edge frequencies, and shows the applications of the slab corner beam splitting and SC-air multilayer acoustic system.

Key words: sonic crystal, negative refraction, wave focusing, partial band gap

中图分类号:  (Acoustical properties of solids)

  • 62.65.+k
43.20.El (Reflection, refraction, diffraction of acoustic waves) 43.20.Mv (Waveguides, wave propagation in tubes and ducts)