Hybrid on-chip quantum photonics combining deterministic telecom single-photon sources, single-photon detectors with ultra-low loss waveguides

集成光子量子技术在复杂现象模拟、量子传感和量子信息处理等研究领域具有广阔的应用前景。目前的提案旨在通过混合组合两个最吸引人的量子光子学平台来彻底改变这些领域：1)用于按需生成非经典光态的半导体量子点。2)硅基光子学是实现超低损耗电路的关键平台。该提案将解决技术方面的问题，如实现多光子学和量子光子学结构的新型优化组合，以及利用远程光源产生多光子态的基本物理方面。我们将研究光子集成电路及其波导和有源光学元件对非经典光态的传播和操纵的影响。IHFG率先实现了在电信波长发射单光子、不可区分光子和纠缠光子的量子点，并显示出按需操作。WWU在3D打印光学器件的实现和波导单光子探测器的实现方面处于世界领先地位。我们实施和研究多源实验的物理特性，对可实现的可扩展性和实验复杂性产生重要影响，远远超出当前的最先进水平。我们的方法可以充分优化基于量子点的光源以及基于硅的电路，而不受制造工艺的限制：非经典光源和硅光子逻辑芯片将分别制造，然后通过3D打印单模波导进行接口。该项目的目标是：1)实现在电信波长运行的明亮、波长可调的非经典光源：这将结合电信波长的先进增长和确定性光刻技术，即ihfg首创的两种功能。2)实现3D打印接口耦合器，用于量子点与硅基电路的高效混合集成。3)实现超低损耗硅基光子电路，该电路专门设计用于与来自电信波长量子点的非经典光一起工作。这将包括波导、分束器、滤波器、移相器和超导单光子探测器。4)远源双光子干涉产生多光子态的研究。5)实现多源芯片，以展示超越当前最先进技术的可扩展性和实验复杂性。6)实现多个按需光源的量子模拟操作，即玻色子采样。实现本项目所强调的目标将对上述量子技术的未来发展产生巨大影响，并拓宽对光子量子物理几个方面的理解。

Integrated photonic quantum technologies represent a promising platform for research fields such as simulation of complex phenomena, quantum sensing and quantum information processing. The current proposal aims at revolutionize these fields by hybrid combination of two of the most appealing platforms for quantum photonics: 1) Semiconductor quantum dots for the on-demand generation of non-classical light states. 2) Silicon-based photonics as a key platform for implementing ultra-low loss circuitry. The proposal will tackle technological aspects, like the realization of a novel optimized combination of multiple photonics and quantum photonics structures, as well as fundamental physics aspects as the generation of multi-photon states employing remote sources. We will investigate the impact of the photonic integrated circuits, their waveguides and active optical elements on the propagation and manipulation of non-classical light states. The IHFG pioneered the realization of QDs emitting single, indistinguishable and entangled photons at telecom wavelength, also showing on-demand operation. The WWU is world leading in the implementation of 3D printed optics and implementation of single-photon detectors on waveguides. We implement and investigate the physics of multi-source experiments with important impact on the achievable scalability and experimental complexity going far beyond current state-of-the-art. Our approach allows to fully optimize the QD-based light sources as well as the Si-based circuitry with no limitations posed by the fabrication processes: the non-classical light source and the silicon photonic logic chip will be fabricated separately, then interfaced via 3D printed single mode waveguides. The goals of the project are:1) Realize bright, wavelength tuneable, sources of non-classical light operating at telecom wavelength: this will be enabled combining advanced growth and deterministic lithography at telecom wavelength, i.e. two capabilities pioneered at the IHFG.2) Implement 3D printed interface couplers for the efficient hybrid integration of QDs with Si-based circuitry.3) Realization of ultra-low loss Si-based photonic circuits specifically designed to operate with non-classical light from telecom-wavelength QDs. This will include waveguides, beam splitters, filters, phase shifters and superconducting single-photon detectors.4) Investigation of the generation of multi-photon states via two-photon interference from remote sources.5) Implementation of multi-source chips in order to demonstrate scalability and experimental complexity beyond current state-of-the-art.6) Implementation of quantum simulation operations, i.e. Boson sampling, with multiple on-demand light sources.Achieving the goals highlighted in this project could have an enormous impact for the future development of the above mentioned quantum technologies and broadening the understanding of several aspects of photonic quantum physics.