Controlling the higher dimensional entanglement between light and cold atoms

控制光原子和冷原子之间的高维纠缠

• 批准号: 18340118
• 负责人: KOZUMA Mikio
• 金额: $ 10.61万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18340118/
• 关键词: DLCZ; Entanglement; Collective mode; Single photon; Laguerre-Gaussian beam; Schmidt number; Laser cooling; Raman scattering; 量子絡み合い; 量子情報処理; collective excitation; 軌道角運動量; 多次元; 集団励起

Higher-dimensional bipartite entangled states enable us to achieve more efficient quantum information processing, for example by enhancing optical data traffic in quantum communications compared to usually employed two-dimensional entanglement between qubits. Such higher-dimensional entangled states can be created by using Laguerre-Gaussian (LG) modes, since photons in LG modes carry orbital angular momenta (OAM) which can be utilized to define an infinite-dimensional Hilbert space. Inspired by the pioneering experiment using parametric down-conversion (PDC), various protocols have been demonstrated using the OAM states of photons. However, PDC is a spontaneous process and the generation time of the entangled photons is completely random. Producing higher-dimensional entanglement between two remote long-lived massive atoms is therefore an important step toward the realization of intricate tasks of quantum information. Here, as the first step, we demonstrated higher dimensional entanglement of OAM states between a collective atomic excitation and a photon. Schmidt number for the atom-photon system was estimated to be 3 through the quantum tomography, which means the system was entangled in 3 X 3 dimensional Hilbert space.

与通常使用的量子比特之间的二维纠缠相比，高维两体纠缠态使我们能够实现更有效的量子信息处理，例如通过提高量子通信中的光数据通信量。这样的高维纠缠态可以通过使用拉盖尔-高斯(LG)模来创建，因为LG模中的光子携带轨道角动量(OAM)，可以用来定义无限维希尔伯特空间。受使用参数下转换(PDC)的开创性实验的启发，利用光子的OAM态已经演示了各种协议。然而，PDC是一个自发过程，纠缠光子的产生时间是完全随机的。因此，在两个遥远的长寿命大质量原子之间产生高维纠缠是实现量子信息复杂任务的重要一步。在这里，作为第一步，我们展示了集体原子激发和光子之间的OAM态的高维纠缠。通过量子层析得到原子-光子系统的施密特数为3，这意味着该系统在3×3维希尔伯特空间中纠缠。

项目成果

Storage and retrieval of a squeezed vacuum

• DOI: 10.1103/physrevlett.100.093601
• 发表时间: 2008-03-07
• 期刊: PHYSICAL REVIEW LETTERS
• 影响因子: 8.6
• 作者: Honda, Kazuhito;Akamatsu, Daisuke;Kozuma, Mikio
• 通讯作者: Kozuma, Mikio

Entanglement of orbital angular momentum states between an ensemble of cold atoms and a photon

• DOI: 10.1103/physreva.74.053809
• 发表时间: 2006-11-01
• 期刊: PHYSICAL REVIEW A
• 影响因子: 2.9
• 作者: Inoue, R.;Kanai, N.;Kozuma, M.
• 通讯作者: Kozuma, M.

Generation of a squeezed vacuum resonant on a rubidium D1 line with periodically poled KTiOPO4.

• DOI: 10.1364/ol.31.002344
• 发表时间: 2006-03
• 期刊: Optics letters
• 影响因子: 3.6
• 作者: T. Tanimura;D. Akamatsu;Y. Yokoi;A. Furusawa;M. Kozuma

Estimation of Three-Dimensional Entanglement between an Atomic Ensemble and a Photon

原子系综和光子之间三维纠缠的估计

• 发表时间: 2007
• 作者: R.Inoue;N.Kanai;T.Yonehara;Y.Miyamoto;M.Koashi;M.Kozuma;M. Kozuma;M. Kozuma;K Honda;R. Inoue
• 通讯作者: R. Inoue

Frequency-filtered storage of parametric fluorescence with electromagnetically induced transparency

• DOI: 10.1103/physreva.76.023812
• 发表时间: 2007-01
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: K. Akiba;K. Kashiwagi;T. Yonehara;M. Kozuma