基本周期对一维复周期光子晶体禁带的影响

Effects of Basic Period of One-Dimensional Biperiodic Holographic Photonic Crystals on the Photonic Band Gap

利用由传输矩阵法得到的一维光子晶体的反射率计算公式,针对具体的一维复周期全息光子晶体的周期结构,计算了光学厚度的改变以及折射率调制周期的改变对光子禁带结构的影响。结果表明,随着光学厚度对比的增大,禁带宽度增大,禁带中心的位置移向长波;随着折射率调制周期参数对比的变化,出现了两个禁带,随着折射率调制周期参数对比的增大,两个禁带之间距离增大,禁带分别移向短波和长波处,短波处禁带宽度减小。在设计光子晶体时,可以根据需要,通过改变光子晶体基本周期结构的参数来实现对光子带隙的控制。

The formulas of the reflectivity in one-dimensional biperiodic holographic photonic crystals were derived by the method of the transfer matrix.With this method,the reflectivity of the one-dimensional holographic photonic crystals was calculated when the optical thickness of the basic period structure of the photonic crystal and the basic period of the refractive index modulation changed.The results show that control of the photonic band gap design can be achieved through changing the basic period length or the optical thickness according to the requirement of the photonic crystals.The position of the gap moves to low frequency and the width of the gap increases as the optical thickness comparison increa sing.As the multiplying power comparison of the refractive index modulation period changes,two gaps appear.With the comparison increasing,the distance of the two gaps increases and the width of the gap of the short wave decreases.