Recently, the group headed by Prof. Zhan Mingsheng, a researcher at the Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, has implemented a new type of magic light trap, a magic light dipole, which imposes a single neutral atomic quantum bit Extend the coherence time hundreds times, from millisecond magnitude to hundred millisecond magnitude. Relevant work is published in Phys. Rev. Lett. 117, 123201, 2016. Single neutral atoms and atomic arrays trapped in light traps are among the many physical candidate systems for promising quantum information processing and quantum simulation. Compared with other systems (such as ions, NV color centers, quantum dots, superconducting lines, etc.), the coupling of neutral atomic system with the external environment is conducive to the preparation of large-scale single-atom arrays. One of the key aspects of quantum information processing in a large-scale neutral-atom register is that the coherence of a single-qubit bit should be well maintained in the transfer of different lattice points in the array. In general, quantum bits are encoded in the clock transitions of two hyperfine levels of Rb atoms. The splitting of the ultrafine level leads to different optical shifts of the atomic levels in the trap, resulting in differential optical frequency shifts. In previous experiments, the differential optical frequency shift was the main factor that led to the loss of coherence in the monatomic quantum bit transfer. The usual method of dynamic decoupling also did not help. This problem greatly limits the realization and application of large-scale neutral atomic quantum information processing platform. He Xiaodong, a research fellow backbone researcher and doctoral student Yang Jiaheng, used the experimental platform of monatomic control to measure the hyperpolarizability of ground state atoms in the vector light field for the first time in the world. Then, by controlling the vector laser field and the faint Interaction, the structure of a single atom magic light dipole trap, effectively eliminating the harmful differential optical frequency shift. In this well, the lifetime of a single qubit increases from a few milliseconds to 225 milliseconds. More importantly, they succeeded in using a moving magical trap to extract a quiescent qubit from another quiescent magical trap, becoming a moving bit and transferring it back into place. By measuring the interference fringes of the moving qubits, it was found that the coherence of the qubits was not lost due to the transfer. The results of this work lay the foundation for the next step to construct a scalable quantum information processor using single atoms trapped in an optical dipole trap array. The research was supported by the State Key Scientific Research Project of Ministry of Science and Technology under the control of the quantum states of single-atom (single-ion) and optical-coupling systems in prisons, supported by the National Natural Science Foundation of China and the pilot project "Atomic-based Precision Measurement Physics" by the Chinese Academy of Sciences. Transfer of Single Atomic Quantum Bits in Ring Optical Lattice
