Zhang Fan, Ren Juanjuan, Duan Xueke, Chen Zhao, Gong Qihuang, Gu Ying
State Key Laboratory for Mesoscopic Physics, Collaborative Innovation Center of Quantum Matter, Department of Physics, Peking University, Beijing 100871, People's Republic of China.
J Phys Condens Matter. 2018 Aug 1;30(30):305302. doi: 10.1088/1361-648X/aacc4f. Epub 2018 Jun 13.
Scalable integrated quantum information network calls for controllable entanglement modulation at subwavelength scale. To reduce laser disturbance among adjacent nanostructures, here we theoretically demonstrate two-qubit entanglement modulated by an evanescent field of a dielectric nanowire in an emitter-AgNP coupled system. This coupled system is considered as a nano-cavity system embedded in an evanescent vacuum. Through varying the amplitude of evanescent field, the concurrence of steady-state entanglement can be modified from 0 to 0.75. Because the interaction between emitters and the nanowire is much weaker than that inside the coupled system, the range of modulation for two-qubit entanglement is insensitive to their distance. The evanescent field controlled entangled state engineering provides the possibility to avoid optical crosstalk for on-chip steady-state entanglement.
可扩展的集成量子信息网络需要在亚波长尺度上进行可控的纠缠调制。为了减少相邻纳米结构之间的激光干扰，在此我们从理论上证明了在发射器 - 银纳米颗粒耦合系统中由介电纳米线的倏逝场调制的两比特纠缠。该耦合系统被视为嵌入倏逝真空中的纳米腔系统。通过改变倏逝场的幅度，稳态纠缠的并发度可以从0修改为0.75。由于发射器与纳米线之间的相互作用比耦合系统内部的相互作用弱得多，两比特纠缠的调制范围对它们之间的距离不敏感。倏逝场控制的纠缠态工程为避免片上稳态纠缠的光学串扰提供了可能性。
