金刚石结构光子晶体的计算与制备

通过平面波法计算金刚石结构光子晶体的禁带特征,得出:当RA=0.16时,禁带宽度最大;当晶格常数a=8.5mm时,对应的最大禁带宽度为3.5GHz,对应的禁带范围为15.3～18.7GHz.利用CAD软件设计了在x,y,z三个方向上的周期数分别为2,4,6的金刚石结构的光子晶体模型,并采用立体印刷技术制备出了17.4mm×36.54mm× 54.32mm的三维微波金刚石光子晶体.最终通过HP网络测试仪对样品的禁带特征进行测试,结果表明;在晶体的＜100》方向上存在频率为14.7～18.5GHz的光子禁带,这与理论值相一致.当电磁波频率为17GHz时,对应的衰减率为-30dB.

Calculation and Fabrication of Photonic Crystal with Diamond Structure

The plane wave propagation method was used to calculate the band gap width of photonic crystals (PCs)with diamond structure．When the lattice constant of the crystal is 8.5mm，the PC has a maximal band gap width of about 3．5GHz．In this case,the frequency of the band gap ranges from 15．3 to 18．7GHz．A computer solid model of a photonie crystal with diamond structure was designed．The epoxy PC was fabricated by stereolithography．The fabricated epoxy PC is 7．40mm×36．54mm×54．32mm in size,and the periodic numbers of the crystal in the x，y，and z directions are 2，4，and 6，respectively．The transmission of microwaves from 10 to 20GHz was measured along the(100)direction by an HP network analyzer.A band gap is formed in the range of 14．7～18．5GHz．The magnitude of the maximum attenuation is as large as-30dB at 17．3GHz,indicating that the fabricated structure works well as a photonic crystal．