Semiconductor Nanowire-based Quantum Light Sources for Quantum Networks

用于量子网络的基于半导体纳米线的量子光源

• 批准号: RGPIN-2018-05438
• 负责人: Dalacu, Dan
• 金额: $ 2.4万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713683
• 关键词: Semiconductor; Nanowire; based; Quantum; Light

The quantum network, whether as a platform to transfer information securely or to share quantum information amongst isolated few-qubit quantum computers, is becoming a reality. To build such a network will require quantum light sources operating at wavelengths where fibre losses are minimum (1310 and 1550nm). In order to achieve sufficient transmission rates, the quantum light sources will need to produce single photons and entangled photon pairs with near-unity efficiency. At present, sources are probabilistic (non-linear crystals or attenuated lasers) which limit efficiencies to ~1%. This program of research proposes to develop on-chip quantum light sources that combine the excellent optical properties of III-V nanowire quantum dots (NW QDs) with the low propagation losses of silicon-based photonics. The long term goal is to provide a scalable solution to generating quantum light with near unity efficiency and available at high repetition rates. Importantly, these photons will be generated at telecom wavelengths compatible with long-haul telecommunication fibres. The availability of such sources will greatly facilitate their implementation in secure quantum networks, where proof of principle has already been demonstrated and a drive for higher key transfer rates is foreseeable. We have an established process whereby individual NW QDs are grown at pre-selected positions on the growth substrate. Importantly, the NW geometry lends itself to a “pick and place” approach for on-chip integration, essentially allowing for the physical manipulation of single quantum emitters. On-chip integration will be achieved by picking up individual NWs from the growth substrate and placing them at specific locations on a substrate prepared with the appropriate photonic circuitry. The research program will start with optimizing source efficiency for devices operating at wavelengths of ~900nm using a SiN on-chip platform (PhD #1). Photonic structures (wavequides, resonators) will be designed for optimal coupling and spontaneous emission rates. The next stage of the project will develope NW sources at telecom wavelengths of 1310nm and 1550nm (PhD#2). These sources will be integrated on-chip using a silicon-on-insulator (SOI) platform. The know-how gained in SiN photonic circuits will be applied to Si to produce telecom wavelength sources operating at GHz emission rates (PhD #1&2). In parallel, a theoretical understanding of the quantum optical properties of NW QDs and their interactions with the environment will be developed (PDF#1). The last stage of the project will explore geometries and growth conditions whereby the III-V NWs can be grown directly on Si with a growth direction parallel to the substrate (PhD #3). If successful, this growth mode can be applied to pre-fabricated SOI photonic circuits to grow telecom wavelength single QDs at pre-selected positions, a truly scalable on-chip platform.

量子网络，无论是作为安全传输信息的平台，还是在孤立的少量子位量子计算机之间共享量子信息的平台，正在成为现实。要建立这样的网络，需要量子光源工作在光纤损耗最小的波长（1310和1550nm）。为了达到足够的传输速率，量子光源需要产生接近统一效率的单光子和纠缠光子对。目前，光源是概率的（非线性晶体或衰减激光），其效率限制在~1%。