| 引用本文: | 魏鹏,葛晓贞,李娜,席在荣.石墨烯量子点和量子比特[J].控制理论与应用,2017,34(11):1437~1445.[点击复制] |
| WEI Peng,GE Xiao-zhen,LI Na,XI Zai-rong.Graphene quantum dots and qubits[J].Control Theory and Technology,2017,34(11):1437~1445.[点击复制] |
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| 石墨烯量子点和量子比特 |
| Graphene quantum dots and qubits |
| 摘要点击 2578 全文点击 1685 投稿时间：2017-08-12 修订日期：2017-10-30 |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| DOI编号 10.7641/CTA.2017.70569 |
| 2017,34(11):1437-1445 |
| 中文关键词 石墨烯量子点 自旋量子比特 电荷量子比特 退相干 |
| 英文关键词 graphene quantum dot spin qubit charge qubit decoherence |
| 基金项目 国家自然科学基金项目(61227902, 61573343), 中国科学院国家数学与交叉科学中心 |
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| 中文摘要 |
| 本文主要回顾了石墨烯量子点的制备以及基于石墨烯量子点自旋和电荷量子比特操作的研究进展, 由于
石墨烯材料相对较轻的原子重量使其具有较小的自旋轨道相互作用, 另外含有核自旋的碳同位素13C在自然界中
的含量大约只占1%, 这使得超精细相互作用(即核自旋和电子自旋相互作用)较弱, 所以石墨烯比其他材料具有较长
的自旋退相干时间, 在量子计算和量子信息中有非常好的应用前景. 本文计算了5种静电约束制备的石墨烯量子点:
1) 扶手型单层石墨烯纳米条带, 2) 单层石墨烯圆盘, 3) 双层石墨烯圆盘, 4) ABC堆积型三层石墨烯圆盘, 5) ABA堆
积型三层石墨烯圆盘. 石墨烯量子点中自旋比特应用的关键是破坏谷简并, 在1)中, 主要是利用边界条件破坏谷简
并, 而2)–5)中是利用外磁场破坏谷简并. 文章进一步介绍了自旋轨道相互作用和超精细相互作用对石墨烯量子点
中自旋操作的影响. |
| 英文摘要 |
| This paper reviews the progress of preparation of graphene quantum dots (GQD) and the operation of spin
qubits and charge qubits based on GQD. Since the graphene material has a relatively light atomic weight resulting to a
smaller spin orbital interaction, and the 13C of carbon isotope containing the nuclear spin accounts for only about 1% in the
nature world, the ultra-fine interaction (i.e., nuclear spin and electron spin interaction) is weaker, which means graphene has
longer spin decoherence time than other materials. Therefore, graphene has promising application in quantum computation
and quantum information. This paper calculates five different types of graphene quantum dots prepared by electrostatic
confinement: 1) graphene nanoribbons with armchair, 2) a disc in monolayer graphene, 3) a disc in bilayer graphene, 4) a
disc in trilayer graphene of ABC stacking, 5) a disc in trilayer graphene of ABA stacking. The key to application of spin
qubits in the graphene quantum dots is the destruction of valley degeneracy. In the first scenario, boundary condition is
used to destroy valley degeneracy, while in other cases, valley degeneracy is destroyed by external magnetic field. Further,
the effect of spin-orbit interaction and hyperfine interaction on operation of spin is introduced in graphene quantum dots. |
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