Coherent Control and Readout of a 25-level Trapped 137Ba+ Ion Qudit

          @misc{ scivideos_PIRSA:24090183,
            doi = {10.48660/24090183},
            url = {https://pirsa.org/24090183},
            author = {},
            keywords = {Quantum Information},
            language = {en},
            title = {Coherent Control and Readout of a 25-level Trapped 137Ba+ Ion Qudit},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2024},
            month = {sep},
            note = {PIRSA:24090183 see, \url{https://scivideos.org/pirsa/24090183}}
          }
          

Abstract

Scaling up the Hilbert space of a quantum computer is essential to demonstrate quantum advantage over classical computing. Other than packing more quantum information carrier in a quantum computing system, one avenue for increasing the quantum computing Hilbert space is by encoding more logical states per quantum information carrier (making it a qudit), rather than a traditional 2-state qubit encoding. Trapped ions typically exhibit multiple (meta)stable electronic energy states that are suitable for logical state encodings and are a suitable platform for qudit applications. In this talk, I present our work on realizing a 25-level trapped 137Ba+ ion qudit, which is the maximal encoding allowed by the single-shot readout protocol that we employ. We show that the harnessing of these additional logical states per ion can be done by just adding a few more lasers to the control system, without any trapping architecture modification compared to a qubit system. I will also present the experimental challenges and limitations, fundamental and technical, relevant to realizing a 25-level trapped 137Ba+ ion qudit.