A scalable quantum computing platform using symmetric-top molecules
A scalable quantum computing platform using symmetric-top molecules
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DOI：
10.1088/1367-2630/ab428d
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发表时间：
2019-05
影响因子：
3.3
通讯作者：
Phelan Yu;L. Cheuk;I. Kozyryev;J. Doyle
中科院分区：
文献类型：
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作者：
Phelan Yu;L. Cheuk;I. Kozyryev;J. Doyle
我们提出了一种新的可扩展的量子计算（QC）平台——碱土金属单甲醇（MOCH3）家族的光学捕获对称顶部分子（STM）阵列。单个 STM 形成量子位，系统可轻松扩展到 100-1000 个量子位。与原子和双原子分子相比，STM 量子位具有理想的 QC 特性。围绕对称顶轴的额外旋转自由度产生了紧密间隔的相反宇称 K 双峰，允许在低电场下完全对准，并且超精细结构自然地提供具有可切换电偶极矩的磁不敏感状态。这些功能大大降低了对电场控制的要求，对环境扰动提供最小的敏感性，并允许随意打开的 2 量子位相互作用。我们详细检查了与我们提出的平台相关的 STM 的内部结构，考虑了包括超精细相互作用在内的完整有效的分子哈密顿量，并确定了可用的 STM 量子位状态。然后，我们研究了 STM 中电偶极相互作用的影响，这不仅指导了高保真门的设计，而且还阐明了 STM 中偶极交换的本质。在实际的实验参数下，我们估计所提出的 QC 平台可以产生 10−3 级别的门误差，接近容错 QC 所需的误差。
We propose a new scalable platform for quantum computing (QC)—an array of optically trapped symmetric-top molecules (STMs) of the alkaline earth monomethoxide (MOCH3) family. Individual STMs form qubits, and the system is readily scalable to 100–1000 qubits. STM qubits have desirable features for QC compared to atoms and diatomic molecules. The additional rotational degree of freedom about the symmetric-top axis gives rise to closely spaced opposite parity K-doublets that allow full alignment at low electric fields, and the hyperfine structure naturally provides magnetically insensitive states with switchable electric dipole moments. These features lead to much reduced requirements for electric field control, provide minimal sensitivity to environmental perturbations, and allow for 2-qubit interactions that can be switched on at will. We examine in detail the internal structure of STMs relevant to our proposed platform, taking into account the full effective molecular Hamiltonian including hyperfine interactions, and identify useable STM qubit states. We then examine the effects of the electric dipolar interaction in STMs, which not only guide the design of high-fidelity gates, but also elucidate the nature of dipolar exchange in STMs. Under realistic experimental parameters, we estimate that the proposed QC platform could yield gate errors at the 10−3 level, approaching that required for fault-tolerant QC.