Xin Maoqing, Png Ching Eng, Lim Soon Thor, Dixit Vivek, Danner Aaron J
Centre for Optoelectronics, Dept. of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore.
Opt Express. 2011 Jul 18;19(15):14354-69. doi: 10.1364/OE.19.014354.
A polymer-infiltrated P-S-N diode capacitor configuration is proposed and a high speed electro-optic phase shifter based on a silicon organic hybrid platform is designed and modeled. The structure enables fast carrier depletion in addition to the second order nonlinearity so that a large electro-optic overlapped volume is achievable. Moreover, the device speed can be significantly improved with the introduction of free carriers due to a reduced experienced transient capacitance. The advantages of the diode capacitor structure are highly suitable for application to a class of low aspect ratio slot waveguides where the RC limitation of the radio frequency response is minimized. According to our numerical results, by optimizing both the waveguide geometry and polarization mode, at least 269 GHz 3-dB bandwidth with high efficiency of 5.5 V-cm is achievable. More importantly, the device does not rely on strong optical confinement within the nano-slot, a feature that gives considerable tolerance in the use of nano-fabrication techniques. Finally, the high overlap and energy efficiency of the device can be applied to slow light or optical resonance media for realizing photonic integrated circuits-based green photonics.
提出了一种聚合物渗透的P-S-N二极管电容器结构，并基于硅有机混合平台设计并建模了一种高速电光移相器。该结构除了具有二阶非线性外，还能实现快速载流子耗尽，从而可实现较大的电光重叠体积。此外，由于引入了自由载流子，有效瞬态电容减小，器件速度可显著提高。二极管电容器结构的优点非常适合应用于一类低纵横比的槽形波导，在这类波导中，射频响应的RC限制最小。根据我们的数值结果，通过优化波导几何结构和偏振模式，在5.5 V-cm的高效率下可实现至少269 GHz的3 dB带宽。更重要的是，该器件不依赖于纳米槽内的强光学限制，这一特性在使用纳米制造技术时具有相当大的宽容度。最后，该器件的高重叠率和能量效率可应用于慢光或光学谐振介质，以实现基于光子集成电路的绿色光子学。
