Entanglement and iSWAP gate between molecular qubits*

I will discuss our recent implementation of a dipolar iSWAP gate between two molecular qubits. Our platform consists of optical tweezer arrays of NaCs molecules, created from individual Na and Cs atoms. We observe sub-millisecond dipolar exchanges between two rotational states, separated by 1.9 μm, exhibiting about ten coherent oscillations. By interrupting the interaction at a quarter-cycle, we confirm the creation of a maximally entangled Bell state with a fidelity of 0.94(3) in trials where both molecules are present. Using motion-rotation coupling, we quantify the temperature along the weakly confined axial dimension of the traps, identifying it as one of the primary sources of decoherence. Lastly, by introducing a third state in a different hyperfine manifold, we implement the iSWAP gate, paving the way for universal quantum computing and quantum simulation in multilevel systems.