Monolithic magneto-optical isolators for on-chip photonic integration

非技术性：光隔离器是电子二极管的光学模拟：它们允许光在一个方向传输，但阻止光在相反方向传播。隔离器是光子集成电路中防止电路不同部分之间的有害串扰和稳定电路运行的重要部件。然而，目前的光隔离器体积庞大，与光子芯片上的集成不兼容。该计划旨在开发基于新型磁光氧化物材料的器件技术，以创建可与硅光子电路直接集成的光隔离器。通过该计划开发的隔离器装置将在光通信和光子信号处理领域产生立竿见影的影响。除了数据通信，它还将在自旋电子学、磁光传感和磁等离子体等新兴应用中发挥关键作用。科学研究将与大规模开放在线课程开发、高中、本科生和研究生培训以及K-12课堂的教育模块设计紧密结合。技术：光隔离器，即只允许光在一个方向传输的设备，是光子集成电路的关键部件，是更大类别的非互易光学设备的例证。尽管光隔离器至关重要，但由于磁光氧化物与普通半导体衬底之间存在较大的晶格常数和热膨胀失配系数，光隔离器的片上集成一直是一项具有挑战性的任务。该计划旨在通过采取涉及材料工程和设备创新的双管齐下的方法来填补这一空白。该计划将开发一种非互易隔离器/环行器器件，使用单片生长的多晶掺CeY铁石榴石作为磁光介质，并采用新的器件设计来提高器件性能。这项研究将导致隔离器器件同时实现单片集成、无源器件操作、大隔离比、最小插入损耗、小占地面积以及优越的操作带宽，从而解决片上光隔离的长期挑战。

Non-technical: Optical isolators are optical analogs of electrical diodes: they allow light to be transmitted in one direction but block light propagation in the opposite direction. Isolators are essential components for photonic integrated circuits to prevent harmful cross-talk between different parts of circuits and stabilize circuit operation. However, current optical isolators are bulky devices not compatible with integration on photonic chips. This program aims to develop the device technologies based on novel magneto-optical oxide materials to create optical isolators amenable to direct integration with silicon photonic circuits. The isolator device developed through this program will have an immediate impact in the fields of optical communications and photonic signal processing. Besides data communication, it will also play a pivotal role in emerging applications such as spintronics, magneto-optical sensing, and magnetoplasmonics. The scientific research will be tightly integrated with Massive Open Online Course development, high school, undergraduate and graduate student training, as well as educational module design for K-12 classrooms.Technical: Optical isolators, devices that allow light transmission in only one direction, are critical components of photonic integrated circuits, and exemplify a larger class of nonreciprocal optical devices. Despite their critical importance, integration of optical isolators on-chip has been a challenging task due to the large lattice constant and coefficient of thermal expansion mismatch between magneto-optical oxides and common semiconductor substrates. This program aims at filling the gap by assuming a two-pronged approach involving both material engineering and device innovation. The program will develop a nonreciprocal isolator/circulator device using monolithically grown polycrystalline Cerium-doped Yttrium Iron Garnet as the magneto-optical medium, and incorporate novel device designs to enhance device performance. The research will lead to an isolator device simultaneously achieving monolithic integration, passive device operation, large isolation ratio, minimal insertion loss, and small footprint, as well as superior operation bandwidth, thus resolving the standing challenge of on-chip optical isolation.