This website requires JavaScript.

Trapped ions beyond carrier and sideband interactions

T. TassisF. L. Semi\~ao
Dec 2022
Trapped ions driven by electromagnetic radiation constitute one of the mostdeveloped quantum technologies to date. The scenarios range fromproof-of-principle experiments to on-chip integration for quantum informationunits. In most cases, these systems have operated in a regime where themagnitude of the ion-radiation coupling constant is much smaller than the trapand electronic transition frequencies. This regime allows the use of simpleeffective Hamiltonians based on the validity of the rotating waveapproximation. However, novel trap and cavity designs now permit regimes inwhich the trap frequency and the ion-radiation coupling constant arecommensurate. This opens up new venues for faster quantum gates and statetransfers from the ion to a photon, and other quantum operations. From thetheoretical side, however, there is not yet much known in terms of models andapplications that go beyond the weak driving scenario. In this work, we willpresent two main results in the scenario of stronger drivings. First, werevisit a known protocol to reconstruct the motional Wigner function and expandit to stronger driving lasers. This extension is not trivial because theoriginal protocol makes use of effective Hamiltonians valid only for weakdrivings. The use of stronger fields or faster operations is desirable sinceexperimental reconstruction methods of that kind are usually hindered bydecoherence. We then present a model that allows the analytical treatment ofstronger drivings and that works well for non-resonant interactions, which aregenerally out of the reach of the previous models.