标题： 锂 tantalate 集成光子学中的阵列波导光栅 显示英文标题

标题： Arrayed waveguide gratings in lithium tantalate integrated photonics

摘要： 阵列波导光栅（AWGs）是用于分离和组合不同波长光的广泛使用的光子组件。 它们在波分复用（WDM）系统中起着关键作用，通过实现多个数据信道在单根光纤上的高效路由，并作为各种光学信号处理、计算、成像和光谱应用的构建模块。 最近，人们越来越关注在铁电材料平台上集成AWGs，因为该平台同时提供高效的电光调制能力，因此有望实现完全集成的WDM发射器。 到目前为止，已经在X切向薄膜铌酸锂（$\mathrm{LiNbO}_3$）平台上进行了若干演示，然而，$\mathrm{LiNbO}_3$的大各向异性使得AWG的设计变得复杂并降低了其性能。 为了解决这一限制，我们采用最近开发的基于薄膜钽酸锂（$\mathrm{LiTaO}_3$）的光子集成电路（PICs），作为一种具有与$\mathrm{LiNbO}_3$相似但显著降低的光学各向异性的材料，作为替代的可行平台。 在这项工作中，我们在晶圆规模上使用深紫外光刻制造了$\mathrm{LiTaO}_3$AWGs。 所制造的AWGs具有100 GHz的通道间隔、小于4 dB的插入损耗和小于-14 dB的串扰。 此外，我们首次在$\mathrm{LiTaO}_3$平台上展示了循环AWG以及用于复用和解复用的AWG对。 这些AWGs的晶圆规模制造不仅确保了均匀性和可重复性，还为在铁电光子集成平台上实现批量制造的集成WDM发射器铺平了道路。 显示英文摘要

摘要： Arrayed Waveguide Gratings (AWGs) are widely used photonic components for splitting and combining different wavelengths of light. They play a key role in wavelength division multiplexing (WDM) systems by enabling efficient routing of multiple data channels over a single optical fiber and as a building block for various optical signal processing, computing, imaging, and spectroscopic applications. Recently, there has been growing interest in integrating AWGs in ferroelectric material platforms, as the platform simultaneously provide efficient electro-optic modulation capability and thus hold the promise for fully integrated WDM transmitters. To date, several demonstrations have been made in the X-cut thin-film lithium niobate ($\mathrm{LiNbO}_3$) platform, yet, the large anisotropy of $\mathrm{LiNbO}_3$ complicates the design and degrades the performance of the AWGs. To address this limitation, we use the recently developed photonic integrated circuits (PICs) based on thin-film lithium tantalate ($\mathrm{LiTaO}_3$), a material with a similar Pockels coefficient as $\mathrm{LiNbO}_3$ but significantly reduced optical anisotropy, as an alternative viable platform. In this work, we manufacture $\mathrm{LiTaO}_3$ AWGs using deep ultraviolet lithography on a wafer-scale. The fabricated AWGs feature a channel spacing of 100 GHz, an insertion loss of < 4 dB and crosstalk of < -14 dB. In addition, we demonstrate a cyclic AWG, as well as a multiplexing and demultiplexing AWG pair for the first time on $\mathrm{LiTaO}_3$ platform. The wafer-scale fabrication of these AWGs not only ensures uniformity and reproducibility, but also paves the way for realizing volume-manufactured integrated WDM transmitters in ferroelectric photonic integrated platforms.