Towards multiqudit quantum processor based on a ^171Yb^+ ion string: Realizing basic quantum algorithms

We demonstrate a quantum processor based on a 3D linear Paul trap that uses ^171Yb^+ ions with 8 individually controllable four-level qudits (ququarts), which is computationally equivalent to a 16-qubit quantum processor. The design of the developed ion trap provides high secular frequencies, low heating rate, which together with individual addressing and readout optical systems allows executing quantum algorithms. In each of the 8 ions, we use four electronic levels coupled by E2 optical transition at 435nm for qudit encoding. We present the results of single- and two- qubit operations benchmarking, generation of a 5-particle Greenberger-Horne-Zeilinger entangled state, and realizing basic quantum algorithms, including Bernstein-Vazirani and Grover's search algorithms as well as H_2 and LiH molecular simulations. Our results pave the way to scalable qudit-based quantum processors using trapped ions.