[微纳光子学前沿报告（4）] Quantitative phononic materials and structures: techniques, optimization, and applications
Mechanical, Materials, and Aerospace Engineering Department
Illinois Institute of Technology
Phononic materials and structures have emerged as powerful media for the fine-tuned control of acoustic and elastic waves. To realize the potential applications, it requires first and foremost the calculation of phononic band structures. In this talk, the formulation and convergence of three fundamental variational principles will be discussed within the context of phononics. A method combining the variational techniques and the plane wave expansion method will be presented establishing its superior computation efficiency as well as its simplicity. The variational techniques will then be combined with gradient based topology optimization for the first ever study of 3-D phononic crystals which exhibit large normalized all-angle all-mode band gaps. Finally, the problem of level repulsion in phononic band structure will be explored and a strategy to distinguish it from normal cross points will be suggested. This process is essential for the correct sorting of the phononic bands and, subsequently, for the accurate determination of mode continuation, group velocities, and emergent properties which depend on them. The sorting method is general and would be directly applicable to other eigenvalue problems where the eigenspectrum needs to be correctly sorted.
Yan Lu is a Ph.D. candidate in Mechanics, Materials, and Aerospace Engineering Department at the Illinois Institute of Technology. His current research focus is on understanding the propagation of waves in phononic crystals through theoretical and high-performance computational tools. He received B.E. in Mechanical Engineering from Xi’an Technological University.
联系人：陆凌 研究员 （Tel：82649203）