Entanglement of Multiple Trapped Ions

M. R. Gaerttner, Arghavan Safavi-Naini, Michael L. Wall +5 more

Gong, Xiaolong, Yang +1 more

Christoph Becher, Jan Benhelm, D. Chek-al-kar +16 more

Kihwan Kim, M.-S. Chang, Rajibul Islam +3 more

We demonstrate tunable spin-spin couplings between trapped atomic ions, mediated by laser forces on multiple transverse collective modes of motion. A sigma_{x}sigma_{x}-type Ising interaction is realized between quantum bits stored in the ground hyperfine clock states of ;{171}Yb;{+} ions. We demonstrate entangling gates and tailor the spin-spin couplings with two and three trapped ions. The use of closely spaced transverse modes provides a new class of interactions relevant to quantum computing and simulation with large collections of ions in a single crystal.

Sackett, D. Kielpinski, Langer +6 more

Wen‐Xing Yang

We propose a scheme to generate a superposition of motional coherent states with arbitrary coefficients on a line in phase space and implement a quantum controlled phase-gate for multiple trapped ions with a single standing-wave laser pulse whose carrier frequency is tuned to the ions transition. In the scheme each ion does not need to be exactly positioned at the node of the standing wave, which is very important from viewpoint of experiment. Furthermore, our scheme may allow the generation of a superposition of coherent states with large mean phonon number for a large number of trapped ions in a fast way by choosing suitable laser intensity. We show that it can also be used to generate maximally entangled states of multiple trapped ions.