Ultra-High-Capacity Optical Communications and Networking: Advanced GaAs-based Waveguide Integration for 1.3/1.55 micron Wavelength Division Multiplexing

该提案是应NSF 01-65“超高容量光通信和网络”的要求提交的。“目前波分复用（WDM）的最新技术水平，光纤C波段（1525-1565 nm）中的~100个信号传输通道，仅使用了可用光纤带宽的一小部分。虽然目前正在开发和部署用于L波段（1565-1605 nm）的掺铒光纤放大器（EDFA），但普遍认识到需要开发用于石英玻璃光纤的低损耗传输“光谱窗口”（1200-1700 nm）的其它部分的系统。目前的C波段系统利用各种方法来混合集成有源InP基光电器件（光子激光源、放大器和检测器）和无源InP或硅上二氧化硅平面光波电路（或PLC，用于复用、解复用和分插功能）。WDM系统中使用的有源和无源元件的更大功能和/或单片集成将降低其成本并加速部署。研究人员最近展示了工作在1310 nm（cw，300 K）和1520 nm（脉冲，300 K）的GalnNAs量子阱异质结构半导体激光器。这些器件克服了InP基异质结构由于低势垒导致的弱载流子限制而固有的性能限制。这一令人兴奋的发展也使GaAs基异质结首次进入光纤通信系统波长。由于GaAs基111-V合金提供的材料参数范围大得多，因此具有用于光通信的有源和无源元件的单片集成的复杂光波电路的潜力比InP材料系统中存在的大得多。特别是，与Al GaAs和InAlP合金的兼容性，可以通过湿热氧化转化为绝缘和透明的低折射率氧化物，为先进的波导集成technology.In这个项目中，GaAs基光子集成电路的WDM应用在光通信的新方法的开发将被探索。A1 GaAs和InA 1 P合金的湿热氧化将被应用于有源和无源波导器件的低损耗波导制造。新型的结构设计和加工方法将结合起来，实现全氧化的A1 GaAs异质结构作为宽带无源脊波导单片集成与有源元件。本机氧化物波导的稀土掺杂将探索使用Pr 3+和Er 3+掺杂的1.3 μ m和1.55 μ m波段放大器，分别。基于相控阵（PHASAR）的WDM器件将在本征氧化物基波导中设计、制造和表征。这将导致圣母大学电气工程系的课程得到加强。

This proposal was submitted in response to the solicitation NSF 01-65 on "Ultra-High Capacity Optical Communications and Networking." The present state-of-the-art in wavelength-division multiplexing (WDM), ~100 signal transmission channels in the fiber C-band (1525-1565 nm), employs only a small fraction of available fiber bandwidth. While erbium-doped fiber amplifiers (EDFAs) for the L-band (1565-1605 nm) are presently being developed and deployed, there is a widely-recognized need to develop systems for other portions of silica glass fiber's low-loss transmission "spectral window" (1200-1700 nm). Present C-band systems utilize various approaches for hybrid integration of both active InP-based optoelectronic devices (photon laser sources, amplifiers, and detectors) and passive InP or silica-on-silicon planar lightwave circuits (or PLCs, for multiplexing, demultiplexing, and add/drop functions). Greater functional and/or monolithic integration of the active and passive components used in WDM systems will reduce their costs and accelerate deployment.Researchers have recently demonstrated GalnNAs quantum well heterostructure semiconductor lasers operating at 1310 nm (cw, 300 K) and 1520 nm (pulsed, 300 K). These devices overcome the performance limitations inherent to lnP-based heterostructures due to weak carrier confinement by low potential barriers. This exciting development also has enabled GaAs-based heterostructures to access optical fiber communication system wavelengths for the first time. The potential for complex lightwave circuitry with monolithic integration of active and passive components for optical communications is much greater than exists in the InP material system due to the much larger range of material parameters afforded by GaAs-based 111-V alloys. In particular, the compatibility with A1GaAs and InAlP alloys, which can be converted through wet thermal oxidation to insulating and transparent low refractive index oxides, provides a significant advantage for advanced waveguide integration techniques.In this project, the development of new approaches for the fabrication of GaAs-based photonic integrated circuits for WDM applications in optical communications will be explored. Wet thermal oxidation of A1GaAs and InA1P alloys will be applied to low-loss waveguide fabrication for both active and passive waveguide devices. Novel structure designs and processing approaches will be combined to realize fully-oxidized A1GaAs heterostructures as broadband passive ridge waveguides for monolithic integration with active components. Rare-earth doping of native oxide waveguides will be explored using both Pr3+- and Er3+-doping for 1.3 um and 1.55 um band amplifiers, respectively. Phased-array (PHASAR) based WDM devices will be designed, fabricated and characterized in native-oxide based waveguides. This will lead to curriculum enhancement in the Department of Electrical Engineering at the University of Notre Dame.