Realization of Robust High-Fidelity Gates for Single-Ion Qubits in a Surface Trap.
Daniel Lobser
Single--ion qubits confined to microfabricated surface traps boast numerous advantages for a scalable quantum computer.The flexibility of modern chip traps supports a variety of exo>c trapping geometries and unprecedented control over individual qubits.Since their incep>on, the viability of chip traps has been met with skep>cism owing to the fact that hea>ng rates would presumably be dominated by surface interac>ons, which play a larger role as a result of the trap's close proximity to the ions.In order to debunk this misconcep>on, we report on the realiza>on of high--fidelity quantum informa>on processing protocols in Sandia's High--Op>cal--Access (HOA) surface trap.Through a number of technical improvements, such as driK control of classical control parameters and our development of a novel "gapless" pulse technique, we have achieved single--qubit gate fideli>es, both laser--and microwave--based, comparable to those found in the best--of--breed electrode traps.Gate Set Tomography (GST) provides an extremely accurate characteriza>on of our gates, including concrete measurements of diamond norm distances.We also demonstrate a realiza>on of the Mølmer--Sørensen two--qubit gate that is stable for several hours.By virtue of this stability, we've performed the first GST measurements in a qutrit basis, which have yielded a two--qubit process fidelity of 99.58( 6)%.Microfabricated Traps at Sandia High Op>cal Access Trap (HOA--2) Single--Qubit Gates Two--Qubit Gate Gate Set Tomography 0 1 0.2 0.
•Jul 10, 2017•0 citations