Exploring nanowire structures for quantum information - a route to discoveries and new technological applications

探索量子信息的纳米线结构——发现和新技术应用的途径

• 批准号: RGPIN-2018-05109
• 负责人: Ruda, Harry
• 金额: $ 2.99万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713506
• 关键词: Exploring; nanowire; structures; quantum; information

Classical computers (CC) use classical physics to encode information in binary bits while quantum computers rely on the laws of quantum mechanics (QM) to process information in qubits qubits may simultaneously be in two states due to superposition, and many such qubits can form strongly correlated systems through entanglement, behaving as a single system. Such QM systems are inherently more powerful than CCs, and with sufficiently large numbers of qubits, can solve problems that are intractable with CCs. The search for a perfect platform that simultaneously satisfies requirements of fast quantum control, long coherence times and scalability to thousands of qubits remains a topic of considerable interest. Recently, a new platform based on semiconductor (S) nanowire (NW) heterostructures (HS) has emerged, with qubits showing the fastest electrical spin manipulation times for single spins in QDs. Moreover, the first signatures of Majorana fermions (MFs), which are their own antiparticles and represent the building blocks for topological qubits, have been very recently reported in such NWs. However, these systems are still in their infancy and typically only function in dilution fridge temperatures. NW HS bring: (a) a virtually unlimited choice of materials for both radial and longitudinal HSs as strain may be relieved by unconfined deformation as they grow, and (b) multiple local metal or superconductor (SC) gates may be defined, together with a global back-gate, to provide scalable qubit systems. This proposal examines NW-based schemes addressing shortcomings of current schemes for a scalable QC platform. MF based qubits, through topological protection, should be virtually immune to environment-based decoherence. However, to host them, ballistic (B) NW HS are key - an area where we have demonstrated control over surface state occupation and backscattering to yield state of the art B-NWs; with sufficient quality B-NWs, long thin NWs can be used to enhance immunity. We propose to harness our recent first reports on proximitized SC with high temperature SCs (HTSC), to potentially bring the technology to near-LN2 temperatures something quite new. Next we will explore scalable systems which can be extended into multi-qubit systems. We will also explore the novel possibility of using HTSC/NW-HS systems for gate controlled radiative emission (and two-photon absorption) of entangled photon pairs at elevated temperatures such devices could provide the means to implement “flying” qubits for scalable quantum processing application. We will also explore an alternative platform for dense qubit registers based on self-assembled electron lattices known as the incipient Wigner lattice. This state with entangled e' (spin antiparallel) pairing, can be explored for its' potential for information transmission, computation and memory.

古典计算机（CC）使用古典物理学在二进制位中编码信息，而量子计算机依靠量子力学定律（QM）来处理量子数限量子中的信息可能只是在两个状态下，并且许多这样的Qubits可以通过单个系统形成近距离的系统。这样的QM系统本质上比CC强大，并且具有足够数量的Qubits可以解决与CC棘手的问题。寻找一个完美的平台，该平台仅满足快速量子控制的要求，长时间的连贯时间和对数千吨位的可扩展性仍然是一个值得关注的话题。最近，出现了一个基于半导体（S）纳米线（NW）异质结构（HS）的新平台，量子位显示了QDS中单旋转的最快的电旋转操作时间。此外，最近在此类NWS中报道了Majorana Fermions（MFS）的第一批签名（MFS），它们是其自己的反粒子，代表了拓扑数量的基础。但是，这些系统仍处于起步阶段，通常仅在稀释冰箱温度下起作用。 NW HS带来：（a）径向和纵向HSS的材料几乎无限的选择，因为应变随着未限制的变形而可以缓解，并且（b）可以将多个局部金属或超导体或超导体（SC）门定义，并可以与全局背门一起定义，以提供可伸缩的qubit系统。该提案考试基于NW的方案解决了当前方案的可扩展QC平台的缺点。通过拓扑保护，基于MF的量子位应实际上是基于环境的破坏的免疫学。但是，要托管它们，弹道（b）NW HS是关键 - 我们已经对表面状态占用和反向散射的控制区域进行了控制，以产生B -NW的最新状态；凭借足够的质量B-NW，可以使用长薄的NWS来增强免疫力。我们建议使用高温SC（HTSC）来利用我们最近的有关接近SC的首次报告，以使该技术具有接近LN2的温度。接下来，我们将探索可扩展的系统，这些系统可以扩展到多Qubit Systems。我们还将探索使用HTSC/NW-HS系统在高温下使用HTSC/NW-HS系统进行纠缠光子对的栅极控制的辐射发射（和两光滥用），这些设备可以提供实施“飞行”量子处理应用的手段。我们还将基于称为初始的Wigner晶格的自组装电子晶格探索一个密集量子寄存器的替代平台。可以探索具有纠缠E'（旋转反平行）配对的状态，可以探索其信息传输，计算和内存的潜力。