Coherent Nanotechnology Quantum Devices for Information Processing

在美国国家科学基金会ECS部门授予的为期一年的探索性研究（SGER）小额赠款中，我们探索了纳米技术器件中相干量子效应的新概念。我们设想了几种基于耦合相干量子现象的新型固态器件，这些器件可能对计算和通信有用，并通过理论研究调查了它们的实用性。有了这个初步的成功，我们现在建议继续这些研究，对这些现象进行更广泛和更精确的分析，并启动一个耦合的实验计划来证明可行性。对于量子计算机来说，最有希望的纳米技术结构是基于交换耦合电子的自旋，这些电子被困在由III-V或硅制成的门控量子点阵列中。所提出的量子计算机能够在相干时间内以10 8 Hz的双量子位操作速率进行10 5次操作。它可以很容易地扩展到大量的元素，在~ 106量子位的顺序上，并且可以利用平面架构进行电重构。毫无疑问，该器件可以使用“国际半导体技术路线图，1999版”中指定的70纳米技术节点所支持的技术制造。我们已经与工业界建立了合作关系，一旦我们证明了这种纳米技术的可行性，他们就会利用这种技术。为了充分检查我们的概念的潜力，我们建议通过分析设备的物理参数来产生所需的能量结构和相邻设备元素之间的耦合强度，通过调查相干性的限制，并通过模拟设备的操作来进行全面的研究，将其作为量子计算机来操作。我们进一步建议进行一个实验计划来制造和测试这些设备的基本原型，以证明可行性。理论和实验研究之间的合作应该会产生一种纳米设备结构，这种结构在技术上是有趣的，并且对商业应用具有潜在的重要意义。这项研究将与一个教育项目相结合，该项目为研究生提供跨学科研究，并为北卡罗莱纳州立大学电气与计算机工程系研究生阶段介绍量子信息过程的课程开发提供支持。

In a one-year small grant for exploratory research (SGER) granted by the ECS Divisionof NSF, we have explored new concepts for coherent quantum effects in nanotechnologydevices. We have conceived of several new solid-state devices based on coupled coherentquantum phenomena that are potentially useful for computing and communications, andinvestigated their practicality through theoretical studies. With this initial success, wenow propose to continue these studies with a more extensive and precise analysis of thephenomena and to initiate a coupled experimental program to show feasibility.The nanotechnology structure that shows most promise for a quantum computer is basedon the spin of exchange coupled electrons trapped in an array of gated quantum dotsfabricated in either III-V or silicon. The proposed quantum computer is capable of 10 5operations within the coherence time at a two-qubit operation rate at 10 8 Hz. It is readilyscalable to a large number of elements, on the order of ~10 6 qubits, and electricallyreconfigurable utilizing a planar architecture. This device is unquestionablymanufacturable using technology enabled by the 70-nm technology node as specified inthe "International Technology Roadmap for Semiconductors, 1999 Edition". We haveestablished collaborations with industry that wish to take advantage of thisnanotechnology once we have shown feasibility.To fully examine the potential of our concepts, we propose to conduct a comprehensivestudy by analyzing the physical parameters of the devices to generate the desired energystructure and coupling strength among neighboring device elements, by investigating thelimitations to coherence, and by simulating the operation of the device to operate it as aquantum computer. We further propose to undertake an experimental program tofabricate and test elementary prototypes of these devices to demonstrate feasibility.Collaboration between the theoretical and experimental studies should result in a nano-devicestructure that is technically interesting and potentially important for commercialuse.This research will be coupled to an educational program that provides interdisciplinaryresearch for graduate students and for the development of courses that introduce quantuminformation processes at the graduate level within the Electrical and ComputerEngineering Department at North Carolina State University.