We demonstrate that the coherence of a single mobile atomic qubit can be wellpreserved during a transfer process among different optical dipole traps(ODTs). This is a prerequisite step in realizing a large-scale neutral atomquantum information processing platform. A qubit encoded in the hyperfinemanifold of $^{87}$Rb atom is dynamically extracted from the static quantumregister by an auxiliary moving ODT and reinserted into the static ODT.Previous experiments were limited by decoherences induced by the differentiallight shifts of qubit states. Here we apply a magic-intensity trappingtechnique which mitigates the detrimental effects of light shifts andsubstantially enhances the coherence time to $225 \pm 21\,\mathrm{ms}$. Theexperimentally demonstrated magic trapping technique relies on the previouslyneglected hyperpolarizability contribution to the light shifts, which makes thelight shift dependence on the trapping laser intensity to be parabolic. Becauseof the parabolic dependence, at a certain "magic" intensity, the first ordersensitivity to trapping light intensity variations over ODT volume iseliminated. We experimentally demonstrate the utility of this approach andmeasure hyperpolarizability for the first time. Our results pave the way forconstructing a scalable quantum-computing architectures with single atomstrapped in an array of magic ODTs.
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