光子晶体应变片的基本原理

光子晶体是人造的周期性结构材料。作为一种复合材料，各组份的介电性质及其空间排列方式决定了光子晶体具有独特的光带隙性能。光子晶体受力变形后必然会改变各组份的空间排列方式，从而改变其光带隙性能。本文利用数值方法模拟了一维光子晶体承受正应变时对其光带隙性能的影响，发现应变的大小与禁带起始波长及截止波长之间存在简单的线性关系。既通过测量光子晶体的光带隙性能就可以得知应变的大小，从而验证了制造光子晶体应变片的可行性。这种应变片的优点是不需要导线相联，而且没有活动部件。

Principles of Photonic Crystal Strain Gauge

Photonic Crystal is a kind of artificial structural mate rials. As a composite, the permmitivities and the packing mode of components determinate its special photonic characteristics, for example, photonic band gap. Mechanical loads can change the packing mode, consequently change its band gap property. The photonic band gap property of one-dimensional photonic crystal under strain was studied numerically. The results show that the strain is proportional to the band edges. Thus, it is possible to deduce the strain by PBG property. Accordingly, the strain gauge made out of Photonic Crystal is possible. The virtue of such strain gauge is wireless, with no moving parts.