講演情報
[16a-P06-2]Effect of doping on modulation bandwidth and absorption loss of electro-optic polymer-infiltrated Si photonic crystal slot nanocavities
〇(PC)Heungjoon Kim1, Bong-Shik Song2, Takashi Asano1, Susumu Noda1 (1.Kyoto Univ., 2.Sungkyunkwan Univ.)
キーワード：
Electro-optic modulation、Photonic nanocavity
In this work, we theoretically investigate the effect of doping density of Si slab on the modulation bandwidth and absorption loss of electro-optic polymer-infiltrated 2D photonic crystal slot nanocavities. To achieve high modulation bandwidth and low free-carrier absorption, we introduce two-level p-type doping consisting of lightly doped region less than 1019 1/cm3 near the cavity and heavily doped region with 6×1019 1/cm3 outside the lightly doped region. We calculate the modulation bandwidth of EO effect and free-carrier absorption loss of the cavity mode as a function of doping level and width of the lightly doped region. As the doping level increases and the width decreases, modulation bandwidth is improved. However, the free-carrier loss also increases, and the total optical loss is determined by the free-carrier loss. We find the appropriate doping level (~ 6×1016 1/cm3) and width (~ 2.2 μm) for achieving high bandwidth (~ 30 GHz) while limiting the free-carrier loss to less than EO polymer’s absorption loss (~ 3×10-6) to maintain high total Q factor (~ 1.6×105). The slot nanocavities with achieved bandwidth and total Q factor are expected to be useful for high-speed and efficient dynamic photon control based on the modulation of a coupled nanocavity system.