Direct measurement of a wave propagating inside a plasma photonic crystal for investigating a novel functional property

为了直接测量在光子晶体中传播的波的电磁场，利用低压放电的存在对气体中的介电常数进行了空间修正。通过定位具有周期性结构的高压电极，在400 kHz射频电源的偏置下，成功地制作了周期性等离子体结构，可以获得大于10×10 cm^-3的等离子体密度。将微波注入到等离子体光子晶体中，在2-3 GHz的频率附近检测到传输带隙的出现。在一维模型中分析了这种周期性等离子体结构中的波传播，结果与实验等离子体光子晶体中观察到的透射率特性基本一致。这将为研究线性和非线性区域的光子晶体物理提供重要的见解。

In order to directly measure the electromagnetic field of the waves propagating inside photonic crystals, the dielectric constant in the argon gas is spatially modified by the presence of the low-pressure discharge. The periodic plasma structure is successfully produced by locating the high-voltage electrode, which has a periodic structure and is biased by a 400 kHz radiofrequency power supply, the plasma density above 10^10 cm^-3 can be obhtained. The microwave is also injected into the plasma photonic crystal and the appearance of the propagation band-gap is detected near the frequency of 2-3 GHz. The wave propagation in such periodic plasma structure is analyzed in one-dimensional model and the results are in fair agreement with the transmittance characteristic observed in the experimental plasma photonic crystal. This will provide important insights into the photonic cyrstal physics in linear and non-linear regime.