Development of optically controlled spin gate using group III-nitrides quantum dots

量子点（QD）是用于存储诸如量子比特（qubit）的量子信息的有吸引力的候选者。在位置控制的异质结构量子点中，电子自旋可以被隔离，使得能够容易地与大规模量子网络中的光子（飞行）量子比特接口。自旋的光学操纵已经成为一种可行的技术，可以在两个单独的量子点中耦合两个自旋量子比特。与垂直耦合相比，横向耦合的QD能够实现单独控制以及允许缩放多量子位处理。III族氮化物量子点具有低介电常数基质、强压电场和大电子/空穴有效质量等独特性质，使得利用它们来构建双量子位控制的相位门成为可能。该合作项目旨在制造和展示具有窄光谱线宽的高纯度，无缺陷的量子点。在这个项目成功的基础上，从长远来看，我们将展示两个或更多个量子点之间的自旋-自旋控制相位（CZ）门。光谱纯的、位点选择性的量子点的开发将是必不可少的第一步，也是实现多功能量子计算功能的关键。为此，申请人（Sharif Sadaf博士和Pei-Cheng Ku博士）利用他们互补的专业知识，技术诀窍，设施和密集的协同作用，旨在提供一个高效和可扩展的平台，用于使用技术上可行的量子点结构制造确定性双量子比特门。国家的最先进的半导体纳米加工和表征技术将被用来实现有针对性的量子点阵列。该项目将对整个量子光子学社区和量子技术的广泛商业化具有价值。我们将为使用半导体QD的量子安全通信网络的发展做出重大贡献。目标成果将通过培训量子光子学领域的高素质人才，使加拿大量子产业受益。这也将在学术界和工业界创造职业生涯，并将有助于加强加拿大在量子通信领域的领先地位。

Quantum dots (QDs) are attractive candidates for storing quantum information such as quantum bits (qubits). In site-controlled, heterostructure QDs, electron spins can be isolated, enabling easy interfacing with photonic (flying) qubits for large-scale quantum networks.Optical manipulation of spins has emerged as a viable technique to couple two spin qubits in two separate quantum dots. In contrast to vertical coupling, laterally coupled QDs enables individual control as well as allow scaling for multi-qubit processing. III-nitride QDs exhibit unique properties including low dielectric constant matrix, strong piezoelectric field, and large electron/hole effective masses, making possible to use them to build two-qubit controlled phase gate. This collaborative project aims to fabricate and demonstrate high-purity, defects-free QDs with narrow spectral linewidths. Building on the success of this project, in the long term, we will demonstrate spin-spin controlled phase (CZ) gate between two or more QDs. The development of spectrally pure, site-selective QDs will be the essential first step and crucial to enabling versatile quantum computational functionalities. To this end, leveraging their complementary expertise, know-how, facilities, and intensive synergy, the applicants (Dr. Sharif Sadaf and Dr. Pei-Cheng Ku) aim to deliver an efficient and scalable platform for making deterministic two-qubit gates using technologically feasible quantum dots structure. State-of-the-art semiconductor nanofabrication and characterization techniques will be utilized to realize the targeted quantum dot array. The project will be valuable for the entire quantum photonics community and the widespread commercialization of quantum technologies. We will provide a significant contribution towards the development of a quantum secure communication network using semiconductor QDs. The targeted outcomes will benefit the Canadian quantum industry through the training of highly qualified personnel in the fields of quantum photonics. This will also create careers in academia and industry, as well as will contribute to strengthening Canada among the leading players in the quantum communication sector.