  The ability to individually and agilely manipulate qubits is crucial for the
scalable trapped-ion quantum information processing. A plethora of challenging
proposals have been demonstrated with the utilization of optical addressing
systems, in which single ions is addressed exclusively by individual laser
beam. However, crosstalk error in optical addressing systems limits the gate
fidelity, becoming an obstacle to quantum computing, especially quantum error
correction. In this work, we demonstrate a low-crosstalk double-side addressing
system based on a pair of acousto-optic deflectors (AODs). The AODs addressing
method can flexibly and parallelly address arbitrary ions between which the
distance is variable in a chain. We employ two 0.4~NA objective lenses in both
arms of the Raman laser and obtain a beam waist of 0.95~$\mu\mathrm{m}$,
resulting in a Rabi rate crosstalk as low as $6.32\times10^{-4}$ when the
neighboring ion separation is about 5.5~$\mu\mathrm{m}$. This agile and
low-crosstalk double-side addressing system is promising for higher-fidelity
gates and the practical application of the quantum error correction.
