Yamamoto Takayuki, Notomi Masaya, Taniyama Hideaki, Kuramochi Eiichi, Yoshikawa Yutaka, Torii Yoshio, Kuga Takahiro
Institute of physics, University of Tokyo, Komaba, Tokyo, Japan.
Opt Express. 2008 Sep 1;16(18):13809-17. doi: 10.1364/oe.16.013809.
We have presented a novel design of a photonic crystal slab (PCS) nanocavity, in which the electric field of the cavity mode is strongly localized in free space. The feature of the cavity is a linear air slot introduced to the center of the mode-gap confined PCS cavity. Owing to the discontinuity of the dielectric constant, the electric field of the cavity mode is strongly enhanced inside the slot, allowing strong matter-field coupling and large interaction volume in free space. Using finite-difference time-domain method, we calculate the properties of the cavity mode as a function of the slot width. The calculated quality factor is still as high as 2 x 10(5) and the mode volume is as small as 0.14 of a cubic wavelength in a vacuum, even if 200-nm-wide slot is introduced to the PCS.
我们提出了一种新型的光子晶体平板（PCS）纳米腔设计，其中腔模的电场在自由空间中强烈局域化。该腔的特点是在模式间隙受限的PCS腔中心引入了一个线性空气槽。由于介电常数的不连续性，腔模的电场在槽内得到强烈增强，从而在自由空间中实现强物质场耦合和大相互作用体积。利用时域有限差分法，我们计算了腔模特性随槽宽度的变化。即使在PCS中引入了200纳米宽的槽，计算得到的品质因数仍高达2×10⁵，模式体积小至真空中立方波长的0.14。
