New Evidence for Dipole–Phonon Quantum Logic in a CaO⁺– Ca⁺ Chain and Progress Toward a Mixed-Species Motional-Mode Interaction Toolbox

Dipole-phonon quantum logic (DPQL) enables new methods for state preparation, measurement, and control of quantum information in molecular ion qubits [1]. We recently demonstrated an experimental implementation of DPQL in a trapped ⁴⁰Ca¹⁶O⁺ – ⁴⁰Ca⁺ ion chain at room temperature [2]. In this poster, we report new results that strengthen the evidence for DPQL and improve the robustness of signal identification. With substantially expanded data sets, we observe DPQL signatures that rise clearly above a well-characterized noise background and remain absent in multiple control measurements, providing strong statistical support for DPQL in this system. In parallel, we are developing and characterizing a programmable interaction toolbox that enables direct and indirect spin–boson or boson-boson couplings involving a set of motional modes. We will also present current platform performance and outline near-term opportunities enabled by this architecture for quantum simulation and precision metrology.