Individual Addressing in a Two-Dimensional Ion Microtrap Array Using Global Laser Beams

Two-dimensional arrays of ions trapped in individual, dynamically tunable microtraps are a promising technology for quantum computation and simulation. To simulate complex quantum systems such as coupled spins on a two-dimensional lattice in an ion microtrap array, it is useful to address individual ions with laser beams to engineer specific quantum states or to perform readout. However, the two-dimensional layout and µm-scale inter-ion distances in such arrays make addressing individual ions with separate laser beams challenging, especially as the number of ions increases. We will discuss the use of micromotion to address and read out selected ions in a three-ion microtrap array. We apply array-site-specific electric fields to trapped ⁹Be⁺ ions, moving them away from their pseudopotential minima to induce a controlled amount of micromotion along the wavevector(s) of the addressing beam(s) ^{1, 2}. This changes the coupling of global laser beams to ions at these sites, enabling site-resolved individual ion addressing. We will present experimental results on fidelity and crosstalk of this micromotion-induced single-ion addressing technique.

¹D. Leibfried, Phys. Rev. A. (1999)

²J.P. Gaebler et al., Phys. Rev. A (2021)