Coherence Preservation of a Single Neutral Atom Qubit Transferred between Magic-Intensity Optical Traps.
We demonstrate that the coherence of a single mobile atomic qubit can be well preserved during a transfer process among different optical dipole traps (ODTs). This is a prerequisite step in realizing a large-scale neutral atom quantum information processing platform. A qubit encoded in the hyperfine manifold of an ^{87}Rb atom is dynamically extracted from the static quantum register by an auxiliary moving ODT and reinserted into the static ODT. Previous experiments were limited by decoherences induced by the differential light shifts of qubit states. Here, we apply a magic-intensity trapping technique which mitigates the detrimental effects of light shifts and substantially enhances the coherence time to 225±21  ms. The experimentally demonstrated magic trapping technique relies on the previously neglected hyperpolarizability contribution to the light shifts, which makes the light shift dependence on the trapping laser intensity parabolic. Because of the parabolic dependence, at a certain "magic" intensity, the first order sensitivity to trapping light-intensity variations over ODT volume is eliminated. We experimentally demonstrate the utility of this approach and measure hyperpolarizability for the first time. Our results pave the way for constructing scalable quantum-computing architectures with single atoms trapped in an array of magic ODTs.
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China.
Jiaheng
J
Yang
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Xiaodong
X
He
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China.
Ruijun
R
Guo
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Peng
P
Xu
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China.
Kunpeng
K
Wang
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.
Cheng
C
Sheng
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Min
M
Liu
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Jin
J
Wang
Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.|Department of Physics, University of Nevada, Reno, Nevada 89557, USA.
Andrei
A
Derevianko
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan 430071, China.|Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Mingsheng
M
Zhan