ExpandQISE: Track 1: Energy Efficient Quantum Control of Robust Spin Ensemble Qubits (EQ2)

非技术描述：可伸缩量子计算中的一个重要问题是以节能的方式对量子比特进行局部寻址。例如，目前的方法使用通过波导传输的不同频率的微波来寻址与不同频率共振的不同量子比特。这样的微波场消耗了大量的能量，将其限制在纳米级是具有挑战性的。该项目将使用纳米级磁体的电压控制来实现高空间分辨率的自旋量子比特的能效和选择性寻址，并将很容易与现有的铸造制造工艺相结合。因此，这个项目将协同地将自旋电子学和量子计算领域结合在一起。该项目团队将在弗吉尼亚联邦大学(VCU)创建一个充满活力的量子信息科学与工程(QISE)项目，并将这项研究与教学和推广相结合，在研究生、本科生和K-12级别教育学生，同时通过合作利用加州大学洛杉矶分校(UCLA)现有的QISE专业知识。这些活动包括开发新的QISE课程、实验室模块，以及通过讲习班和暑期实习为QISE中代表性不足的学生提供K-12外展服务。技术描述：该项目将模拟和演示利用近邻自旋量子比特的拉莫尔频率的电场驱动的纳米磁体对量子比特的高度局域化控制，以实现最先进的保真度和高能量效率的单量子比特量子门。为了实现上述研究愿景，该项目将(1)模拟和实验演示纳米级磁体的电压控制，使用异质结构在有限的纳米体积内为高保真的单自旋量子比特门局部产生所需的磁场脉冲，(2)证明这种纳米磁体的电压控制磁化动力学可以控制可光学读取的高保真的钻石中的NV自旋量子比特中心，和(3)模拟由10-100个自旋组成的介观自旋系综的集体动力学(为了增加信噪比，并可能通过自旋相互作用来减少退相而进行纠错)，并证明了电压控制纳米磁体可以高保真地控制这样的自旋系综。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。

Non-technical Description:An important problem in scalable quantum computing is to locally address qubits in an energy-efficient manner. Current approaches, for example, use microwaves at different frequencies conveyed through waveguides to address different qubits that are resonant to different frequencies. Such microwave fields consume significant energy and their confinement to the nanometer scale is challenging. This project will use voltage-control of nanoscale magnets for energy efficient and selective addressing of spin qubits with high spatial resolution and will be easy to integrate with existing foundry manufacturing processes. Thus, this project will synergistically bring together the fields of spintronics and quantum computing. The project team will create a vibrant Quantum Information Science and Engineering (QISE) program at Virginia Commonwealth University (VCU) and integrate this research with teaching and outreach to educate students in QISE at the graduate, undergraduate, and K-12 levels while leveraging existing QISE expertise at the University of California, Los Angeles (UCLA) through collaboration. Such activities include developing a new QISE course, lab modules, and K-12 outreach through workshops and summer internships for underrepresented students in QISE. Technical Description:This project will simulate and demonstrate highly localized control of qubits using nanomagnets driven by an electric field at the Larmor frequency of proximally located spin qubits to implement single-qubit quantum gates with state-of-the-art fidelities and high energy efficiency. Towards realizing the above research vision, the project will (1) simulate and experimentally demonstrate voltage control of nanoscale magnets using heterostructures to generate the desired magnetic field pulses locally in a confined nanoscale volume for high fidelity single spin qubit gates, (2) demonstrate that the voltage-controlled magnetization dynamics of such nanomagnets can control NV spin qubit centers in diamond with high fidelity that can be read optically, and (3) simulate the collective dynamics of mesoscopic spin ensembles comprising 10-100 spins (for an increased signal to noise ratio and possibly error correction through spin interaction to reduce dephasing) and demonstrate that voltage-controlled nanomagnets can control such an ensemble of spins with high fidelity.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.