Electro-Optic and All-Optic Collinear Asymmetrical Directional Coupler

介绍了一种新的器件结构，采用In2O3/InxSn1-xOy异质结构薄膜的共线非对称定向耦合器，它将降低获得全强度调制所需的功耗，可适应任何衬底，具有高复用能力，并有可能产生新的电光和全光器件系列。传统的共面定向耦合器必须具有完全相等宽度的波导，这是非常难以实现的。我们将通过可变导模有效折射率技术消除严格的波导通道公差要求。不同于III-V和II-VI化合物半导体异质结构，In2O3/InxSn1-xOy薄膜可以生长在任何表面。因此，有源器件可以建立在衬底材料阵列上。In2O3/InxSn1-xOy具有400 nm至中红外的透明带宽。大量的光波长也可以复用。最后，通过注入载流子实现了In2O3/InxSn1-xSn1-xOy薄膜的折射率调制。因此，电光器件和全光器件都可以基于这个新概念来实现。载流子注入的折射率调制比线性电光效应的折射率调制高两个数量级。期望相互作用长度与多量子阱器件兼容。

A new device structure, a collinear asymmetrical directional coupler using In2O3/InxSn1-xOy heterostructure thin film, is introduced which will decrease the power consumption needed to obtain full intensity modulation, is adaptable to any substrate, has a high multiplexing capability, and will potentially give yield to a new line of both electro-optic and all-optic devices. Conventional coplanar directional couplers must have waveguides of exactly equal widths which is extremely difficult to achieve. We will eliminate the stringent waveguide channel tolerance requirements through a variable guided mode effective index technique. Unlike the III-V and II-VI compound semiconductor heterostructure, the In2O3/InxSn1-xOy film can be grown on any surface. Therefore, an active device can be built on an array of substrate materials. The In2O3/InxSn1-xOy has a transparent bandwidth from 400 nm to mid-infrared. A large number of optical wavelengths can also be multiplexed. Finally, the index modulation of In2O3/InxSn1-xSn1-xOy film is brought about by carrier injection. Consequently, both electro-optic and all optical devices can be realized based on the novel concept. The index modulation with carrier injection is two orders of magnitude higher than with the linear electro-optic effect. The interaction length is expected to be compatible with multi-quantum well devices.