Deterministic and tunable quantum dots based on bilayer semiconductor heterostructures

基于双层半导体异质结构的确定性可调量子点

• 批准号: 2054572
• 负责人: John Schaibley
• 金额: $ 39万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-15 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2054572&HistoricalAwards=false
• 关键词: Deterministic; tunable; quantum; dots; based

Quantum dots are nanoscale structures capable of controllably trapping single electrons. These nanoscale electronic devices exhibit quantum mechanical behaviors which can potentially be used to realize quantum computing devices that offer significant computational advantages over current computing architectures. Furthermore, these trapped electrons can act as quantum light sources, which would help enable quantum devices that are secure against cyber-attacks. Over the past 20 years, optically driven quantum dots have been pursued in a variety of semiconductor systems and have been shown to exhibit many of the necessary properties that are required for quantum computing architectures. However, previous quantum dot architectures have not been able to reliably scale up to a large number of quantum dots with sufficient control to be used for quantum devices. In this project, a new type of quantum dot will be engineered based on two-dimensional materials which are only a few atomic layers thick. The proposed quantum dot consists of two semiconductor monolayers stacked together to realize electrons whose energies can be tuned electrically. Using nanofabrication techniques, small holes will be patterned onto the device, which will form the quantum dot. The quantum properties of the quantum dot will be measured using state-of-the-art optical techniques. This new quantum dot architecture has the potential to overcome previous limitations because it offers control over the quantum dot position and energy. This research aligns with the NSF Big Idea of the Quantum Leap: Leading the Next Quantum Revolution by developing material systems that have the potential to enable these new quantum information technologies. Furthermore, the project strengthens the STEM workforce both directly and indirectly by training and mentoring graduate, undergraduate, and high school students through the proposed research, and by encouraging interest in STEM at the high school level in southern Arizona. The overarching project objective is to achieve deterministic, scalable, and tunable quantum information devices based on optically driven spin-valley electrons in novel two-dimensional (2D) material heterostructures. Specifically, a nano-patterned gate engineering architecture will be explored to realize localized quantum states of single electrons and single excitons in MoSe2-WSe2 heterostructures. This architecture will enable electrostatic quantum dots (eQDs) that are predicted to exhibit the desired high levels of tunability, spectral stability, and long coherence times necessary for spin-valley qubits with applications in quantum processing and quantum information storage. In solid state systems, QDs can support single photon emitter behavior and, once charged, establish a long-lived, ground-state spin qubit that can be coherently controlled optically and potentially realize long range interactions via entangled photons. Although other solid-state spin systems (III-V QDs, vacancy centers) have demonstrated the single qubit requirements, scaling these solid-state qubits to large numbers has been limited by inhomogeneity in QDs and photonic integration challenges for vacancy centers. These challenges motivate the development of a new solid-state spin qubit system that is both deterministic and tunable—allowing for control of both the spatial placement and qubit energy. In this project, novel eQD structures will be engineered and fabricated. The eQD quantum states and coherence properties will be measured using a combination of far-field spectroscopy and near field scanning optical microscopy. Coherent control of single spin-valley qubits will be demonstrated using coherent nonlinear spectroscopy.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.

量子点是能够可控地捕获单个电子的纳米级结构。这些纳米级电子设备表现出量子力学行为，有可能用于实现量子计算设备，与当前的计算架构相比，量子计算设备具有显着的计算优势。此外，这些被捕获的电子可以充当量子光源，这将有助于使量子设备能够抵御网络攻击。在过去的 20 年里，光学驱动的量子点已在各种半导体系统中得到应用，并已被证明具有量子计算架构所需的许多必要特性。然而，以前的量子点架构还无法可靠地扩展到大量量子点，并具有足够的控制能力以用于量子器件。在这个项目中，将基于只有几个原子层厚的二维材料来设计一种新型量子点。所提出的量子点由两个堆叠在一起的半导体单层组成，以实现可以电调节能量的电子。使用纳米加工技术，小孔将在器件上形成图案，从而形成量子点。量子点的量子特性将使用最先进的光学技术进行测量。这种新的量子点架构有可能克服以前的限制，因为它提供了对量子点位置和能量的控制。这项研究与 NSF 量子飞跃的大理念相一致：通过开发有潜力实现这些新量子信息技术的材料系统，引领下一次量子革命。此外，该项目通过拟议的研究来培训和指导研究生、本科生和高中生，并鼓励亚利桑那州南部高中对 STEM 的兴趣，从而直接和间接地加强 STEM 劳动力队伍。该项目的总体目标是在新型二维（2D）材料异质结构中实现基于光驱动自旋谷电子的确定性、可扩展和可调谐的量子信息器件。具体来说，将探索纳米图案栅极工程架构，以实现MoSe2-WSe2异质结构中单电子和单激子的局域量子态。这种架构将使静电量子点（eQD）能够表现出所需的高水平可调谐性、光谱稳定性和自旋谷量子位在量子处理和量子信息存储中的应用所需的长相干时间。在固态系统中，量子点可以支持单光子发射器行为，并且一旦充电，就可以建立一个长寿命的基态自旋量子位，该量子位可以进行光学相干控制，并有可能通过纠缠光子实现长程相互作用。尽管其他固态自旋系统（III-V量子点、空位中心）已经证明了单个量子位的要求，但将这些固态量子位扩展到大量量子点一直受到量子点的不均匀性和空位中心的光子集成挑战的限制。这些挑战推动了新型固态自旋量子位系统的开发，该系统既具有确定性又可调节，从而可以控制空间布局和量子位能量。在该项目中，将设计和制造新型 eQD 结构。 eQD 量子态和相干特性将使用远场光谱和近场扫描光学显微镜的组合进行测量。单自旋谷量子位的相干控制将使用相干非线性光谱进行演示。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Localized Interlayer Excitons in MoSe2-WSe2 Heterostructures without a Moiré Potential

无莫尔势的 MoSe2-WSe2 异质结构中的局域层间激子

• DOI: 10.48550/arxiv.2203.08052
• 发表时间: 2022
• 期刊: ArXivorg
• 作者: Mahdikhanysarvejahany, Fateme;Shanks, Daniel N.;Klein, Matthew;Wang, Qian;Koehler, Michael R.;Mandrus, David G.;Taniguchi, Takashi;Watanabe, Kenji;Monti, Oliver;LeRoy, Brian J.
• 通讯作者: LeRoy, Brian J.

Nanoscale Trapping of Interlayer Excitons in a 2D Semiconductor Heterostructure

• DOI: 10.1021/acs.nanolett.1c01215
• 发表时间: 2021-06-24
• 期刊: NANO LETTERS
• 影响因子: 10.8
• 作者: Shanks, Daniel N.;Mahdikhanysarvejahany, Fateme;Schaibley, John R.
• 通讯作者: Schaibley, John R.

Single-exciton trapping in an electrostatically defined two-dimensional semiconductor quantum dot

• DOI: 10.1103/physrevb.106.l201401
• 发表时间: 2022-06
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Daniel N. Shanks;Fateme Mahdikhanysarvejahany;M. Koehler;D. Mandrus;T. Taniguchi;Kenji Watanabe

Interlayer Exciton Diode and Transistor

• DOI: 10.1021/acs.nanolett.2c01905
• 发表时间: 2022-08-24
• 期刊: NANO LETTERS
• 影响因子: 10.8
• 作者: Shanks, Daniel N.;Mahdikhanysarvejahany, Fateme;Schaibley, John R.
• 通讯作者: Schaibley, John R.