Light cages meet metasurfaces: On-chip twisted light applications enabled by direct laser writing

光笼遇见超表面：通过直接激光写入实现片上扭曲光应用

• 批准号: 500262769
• 负责人: Professor Dr. Markus A. Schmidt
• 金额: --
• 依托单位: Leibniz-Institut für Photonische Technologien (IPHT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/500262769?language=en
• 关键词: Light; cages; meet; metasurfaces; chip

Due to its unique properties in terms of physics and applications, twisted (chiral) light with both spin and orbital angular momentum is a highly topical field of research. From a waveguide perspective, twisted optical fibers exhibit fascinating phenomena such as helical Bloch modes or strong circular dichroism. Twisting rates achieved, however, are rather small, only leading to a small perturbative-type influence on mode formation. From the perspective of wavefront shaping, geometric metasurfaces enable control over orbital angular momentum states, yet often suffer from significant cross talk for example in a context of multiplexing.A recently introduced implementation approach for sophisticated photonic structures is 3D nanoprinting using Direct Laser Writing (DLW), offering unique advantages for waveguides and metasurfaces. Here, novel on-chip hollow-core waveguides - so-called light cages - and metasurfaces with access to the additional height degree of freedom have been jointly demonstrated by the applicants.The proposed project targets to explore the generation, guidance and manipulation of light interacting with nanoprinted twisted photonic structures including light cages, chiral metasurfaces and their combination. The project aims to (i) understand the properties of light propagating inside twisted light cages and controlled via chiral metasurfaces, (ii) unlock the potential of DLW to realise twisted functional photonic structures, and (iii) to evaluate whether the combination of chiral metasurfaces and twisted light cages results in a novel photonic platform to reach previously inaccessible physics and applications. To give some examples, DLW principally enables light cages with exceptionally high twist rates and unexplored geometries. For metasurfaces, the height degree of freedom offers full control not only over geometric but also over the propagation phase and therefore the complex amplitude, and via sophisticated shapes also enables intrinsically chiral unit cells. Equally important for our work, DLW allows for direct implementation of metasurface-interfaced twisted light cages in a single fabrication step.Overall, the project will uncover novel physics concerning generation, guidance and manipulation of light interacting with twisted photonic structures. Potential applications that are evaluated within the context of this project will include chiral molecular on-chip sensing, OAM-assisted multiplexing or atomic magnetometry.

由于其在物理和应用方面的独特性质，具有自旋和轨道角动量的扭曲（手性）光是一个非常热门的研究领域。从波导的角度来看，扭曲光纤表现出迷人的现象，如螺旋布洛赫模式或强圆二色性。然而，实现的扭转率是相当小的，只导致一个小的扰动型模式形成的影响。从波前成形的角度来看，几何元表面能够控制轨道角动量状态，但通常会遭受严重的串扰，例如在多路复用的背景下。最近推出的复杂光子结构的实现方法是使用直接激光写入（DLW）的3D纳米打印，为波导和元表面提供独特的优势。在这里，新的芯片上空芯波导-所谓的光笼-和超颖表面与访问额外的高度自由度已经由申请人共同展示。拟议的项目的目标是探索光的产生，引导和操纵与纳米印刷扭曲光子结构，包括光笼，手性超颖表面及其组合相互作用。该项目旨在（i）了解光在扭曲光笼内传播并通过手性超颖表面控制的特性，（ii）解锁DLW实现扭曲功能光子结构的潜力，以及（iii）评估手性超颖表面和扭曲光笼的组合是否会产生一种新的光子平台，以达到以前无法实现的物理和应用。举例来说，DLW主要实现具有极高扭曲率和未探索几何形状的轻质笼。对于超颖表面，高度自由度不仅提供了对几何形状的完全控制，而且还提供了对传播相位的完全控制，因此还提供了对复振幅的完全控制，并且通过复杂的形状还实现了固有的手性晶胞。对于我们的工作同样重要的是，DLW允许在单个制造步骤中直接实现超表面接口的扭曲光笼。总的来说，该项目将揭示关于光与扭曲光子结构相互作用的产生，引导和操纵的新物理。在本项目范围内评估的潜在应用将包括手性分子芯片传感、OAM辅助多路复用或原子磁力测定。