Control and Entanglement of Rydberg Atom Qubits near a Nanophotonic Device

Rydberg atoms in optical tweezers have shown promise as a platform for quantum computing. However, Rydberg atoms lack a natural form of quantum networking and fast readout. Which would increase their prospects for scalability, as well as, their ability to perform in-situ quantum error correction. We investigate the use of an optical interface in the form of a silicon nitride photonic crystal cavity (PCC). In our previous work we have demonstrated fast non-destructive state readout through the PCC and the ability to coherently move entangled atoms from the PCC to freespace. In order to determine the viability of a Rydberg atom PCC interface, we characterize the coherence of Rydberg atoms in the presence of the PCC. We find that the Rydberg atom coherence quickly breaks down when we are closer than 100s of microns from the nanophotonic cavity due to the large charge on the PCC and it's charge fluctuation. However, we can recover coherence through decoupling sequences. These results support further investigation of integrating rydberg atom quantum computers with nanophotonic interconnects.