Bao, YichengYu, Scarlett S.Anderegg, LoicChae, EunmiKetterle, WolfgangNi, Kang-KuenDoyle, John M.2023-12-202023-12-08Bao, Yicheng, Scarlett S. Yu, Loic Anderegg, Eunmi Chae, Wolfgang Ketterle, Kang-Kuen Ni, John M. Doyle. "Dipolar spin-exchange and entanglement between molecules in an optical tweezer array." Science 382, no. 6675 (2023): 1138-1143. DOI: 10.1126/science.adf89990036-80751095-9203https://nrs.harvard.edu/URN-3:HUL.INSTREPOS:37377561Ultracold polar molecules are promising candidate qubits for quantum computing and quantum simulations. Their long-lived molecular rotational states form robust qubits and the long-range dipolar interaction between molecules provides quantum entanglement. Here, we demonstrate dipolar spin-exchange interactions between single CaF molecules trapped in an optical tweezer array. We realize the spin-1/2 quantum XY model by encoding an effective spin-1/2 system into the rotational states of the molecules, and use it to generate a Bell state through an iSWAP operation. Conditioned on the verified existence of molecules in both tweezers at the end of the measurement, we obtain a Bell state fidelity of 0.89(6). Employing interleaved tweezer arrays, we demonstrate single site molecular addressability.en-USMultidisciplinaryJournal Article2023-12-2010.1126/science.adf8999