RAISE: TAQS: Engineering high quality, practical qubits in diamond

钻石等半导体中的色心已经成为实现可扩展量子技术(量子计算机和量子互联网)的一个有前途的平台。然而，到目前为止，大多数结果都是实验室中不切实际的概念验证演示，并且依赖于超低温下的实验，由于系统效率较低，导致实验时间较长。为了实现真正的量子飞跃，这项研究将开发一种低噪声、高保真和高效、实用和可扩展的量子技术，它在更友好的环境中运行，因此可能无处不在。这项拟议的研究将影响量子工程和设备、基础物理和材料科学。跨学科团队由量子光学理论和实验、材料加工和纳米制造、量子技术和优化光子学设计等领域的世界领先专家组成。该项目包括与研究相结合的教育和外联活动，这些活动已经由私人投资机构发起，包括积极招募少数民族和妇女从事科学和工程职业，开发新班级，本科生研究和咨询，以及参与针对K-12学生和教师的外联方案。该项目致力于基于具有反转对称性的钻石色心(硅、锗和锡空位)设计高质量、实用的量子比特，这些色心比非对称色心(如氮空位)对环境的影响更强。这项工作将集中在设计具有良好光学界面的高质量量子比特，其中应变以及光学和声学声子态密度将通过制备方法(如应力源沉积、退火)和结构几何来局部控制。其目标是提高量子效率，并在高温(可能高达~77K)下实现长相干时间。此外，光子优化方法将被用来提高量子电路的效率，并增加功能的、光学互连的芯片上量子设备的产量。这项拟议的努力有可能通过在更友好的环境中进行可扩展的实验来彻底改变量子工程和腔QED领域。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Color centers in semiconductors, such as diamond, have emerged as a promising platform for implementation of scalable quantum technologies (quantum computers and quantum internet). However, most of the results so far are impractical, proof-of-concept demonstrations in laboratories, and rely on experiments at ultracold temperature, with long experiment times resulting from poor system efficiencies. In order to enable a true quantum leap, this research will develop a low noise, high fidelity and efficiency, practical and scalable quantum technology which operates in friendlier environments and could thus be ubiquitous. The proposed research will impact quantum engineering and devices, fundamental physics, and materials science. The interdisciplinary team consists of world leading experts in the areas of quantum optics theory and experiment, materials processing and nanofabrication, quantum technologies, and optimized photonics design. The project includes educational and outreach activities integrated with research, which the PIs have already initiated, including active recruitment of minorities and women for science and engineering careers, development of new classes, undergraduate research and advising, and participation in outreach programs for K-12 students and teachers. Technical descriptionThis project is focused on engineering high quality, practical qubits based on diamond color centers with inversion symmetry (Si, Ge, and Sn vacancy) which are more robust to their environment than their non-symmetric counterparts (such as nitrogen vacancy). The effort will be focused on engineering high quality qubits with excellent optical interfaces, where strain, as well as optical and acoustic phonon density of states will be locally controlled by fabrication methods (such as deposition of stressors, annealing) and by structure geometry. The goal is to increase quantum efficiency and enable long coherence times at elevated temperatures (potentially up to ~77K). In addition, photonic optimization methods will be used to increase efficiency of quantum circuits and to increase the yield of functional, optically interconnected quantum devices on chip. The proposed effort has the potential to revolutionize the field of quantum engineering and cavity QED by enabling scalable experiments in friendlier environments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.