Quantum Algorithms on a Programmable Ion Trap Quantum Computer
JQI & NIST
Trapped ions are a highly advanced platform for implementing quantum circuits. They provide standard pairs of magnetic field insensitive "atomic clock" states as qubits with unsurpassed coherence times and optical schemes for near-unity preparation and measurement, as well as strong Coulomb interactions to generate entanglement.
We present a modular architecture comprised of a chain of trapped 171Yb+ ions with individual Raman beam addressing and individual readout. We employ a pulse-shaping scheme  to use the transverse modes of motion in the chain to produce entangling gates between any qubit pair. This creates a fully connected system which can be configured to run any sequence of single- and two-qubit gates, making it in effect an arbitrarily programmable quantum computer .
To demonstrate the universality of this setup, we present experimental results from different quantum algorithms on five ions including the Bernstein-Vazirani and hidden Shift algorithms which allow the single-shot determination of an oracle function, as well as the Quantum Fourier Transform which we use to implement a Period Finding as well as a Phase Estimation protocol, the latter being a key ingredient in prime factorization. We also discuss this architecture in relation to the recently publicized IBM cloud device .
 T. Choi et al., Phys. Rev. Lett. 112, 19502 (2014)
 S. Debnath et al., Nature 536, 63 (2016)
This work is supported by the ARO with funding from the IARPA LogiQ program and the AFOSR MURI on Quantum Measurement and Verification.
Hosted by Mohammad Hafezi and Charles Clark.