Intersubband Electro-optic modulators

子带间电光调制器

• 批准号: 1928806
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1928806
• 关键词: Intersubband; Electro; optic; modulators

Optical modulators are the key elements of optical transceivers. The multi-billion market of optical transceivers increasingly demands devices with higher performance with sustainable cost. Indium phosphide (InP) technology need to deliver next generation optical-communication systems beyond 100 G, and recent InP photonics innovations indeed promise high performance in terms of bandwidth, power consumption, and port density. In current generation InP based electro-absorption modulators that operate by interband absorption, the absorption recovery time reported is limited to 5 ps. On the other hand, intersuband transitions in InP based quantum wells is quite promising to achieve ultra-high speed optical modulation due to its intrinsic characteristics of sub-picosecond carrier relaxation time and large optical nonlinearities. Substantial improvements in the bandwidth can also be expected for devices operated by intersubband transitions along with other parallel processes, including thermionic emission and tunnelling. Moreover, the devices based on intersubband transitions take advantages of conventional III-V materials and the advanced InP engineering capability and reliable device technology, and thus different photonic components can be simply integrated on a single chip, leading to higher integration density and lower cost. Last but not least, standard interband EAMs are temperature dependent because the band edge moves with temperature at a rate around 0.5nm/C, while in intersubband electro-optic modulators, this rate is estimated to be reduced by one order, i.e. transition energy will move at around 0.05 nm/C, making it suitable for use as an uncooled device.In this project, the potential of intersubband electro-optic modulators on InP substrates will be explored for the next generation data communication systems, which is aligned with the EPSRC thematic area, Information and communication technologies (ICT). Aims and objectives:The studentship project will focus on developing high speed modulators based on intersubband transitions. The main objectives of the project are:Objective 1: To understand the electro-optic effects of intersubband transitions in InGaAs/AlAsSb QWs. Objective 2: Develop high quality quantum wells with abrupt interface and high crystal quality that are optically active at 1550 nm. Objective 3: Optimise the device structure. Achieve high electro-optic coefficient and high speed modulation of the quantum wells.Potential applications and benefits:During the early stage of this project, both industrial and academic supervisors will guide the PhD student to develop necessary knowledge in this field by extensive literature review. Facility access and equipment will be provided for the training of the PhD student during the project, including epitaxy growth equipment and device processing cleanroom. The PhD student will also be trained for a number of material and device characterization equipment. At the end of the project, a new type of electro-optic modulator will be developed that can make the data communication faster and advance the ICT industry in UK. The PhD student will be provided the opportunities to attend domestic and international conferences to disseminate any scientific advance made in the project.

光调制器是光收发机的关键部件。数十亿美元的光收发器市场越来越需要具有可持续成本的更高性能的设备。磷化铟（InP）技术需要提供超过100 G的下一代光通信系统，而最近的InP光子学创新确实有望在带宽、功耗和端口密度方面实现高性能。在通过带间吸收操作的当前一代InP基电吸收调制器中，所报道的吸收恢复时间限于5 ps。另一方面，InP基威尔斯量子阱中的子带间跃迁由于其亚皮秒载流子弛豫时间和大的光学非线性特性，在实现超高速光调制方面具有很大的潜力。对于通过子带间跃迁沿着其他并行过程（包括电子发射和隧穿）操作的器件，也可以预期带宽的实质性改善。此外，基于子带间跃迁的器件利用了传统的III-V族材料和先进的InP工程能力以及可靠的器件技术，因此不同的光子器件可以简单地集成在单个芯片上，从而导致更高的集成密度和更低的成本。最后但并非最不重要的是，标准带间EAM是温度相关的，因为带边缘以约0.5nm/C的速率随着温度移动，而在子带间电光调制器中，该速率估计将降低一个数量级，即跃迁能量将以约0.05nm/C移动，使其适合用作非冷却设备。将探索InP基片上的子带间电光调制器在下一代数据通信系统中的潜力，这与EPSRC的主题领域信息和通信技术（ICT）是一致的。目的与目标：本研究计画将著重于发展以子带间转换为基础的高速调变器。本研究的主要目的是：目的1：了解InGaAs/AlAsSb量子阱子带间跃迁的电光效应。目标2：研制具有突变界面和高晶体质量的高质量量子威尔斯阱，这些量子阱在1550 nm处具有光学活性。目标3：优化设备结构。实现量子威尔斯的高电光系数和高速调制。潜在的应用和好处：在本项目的早期阶段，工业和学术导师将指导博士生通过广泛的文献回顾来发展该领域的必要知识。在项目期间，将为博士生的培训提供设施和设备，包括外延生长设备和器件加工洁净室。博士生还将接受一些材料和器件表征设备的培训。在项目结束时，将开发一种新型的电光调制器，可以使数据通信更快，并推动英国ICT产业的发展。博士生将有机会参加国内和国际会议，以传播该项目中取得的任何科学进展。