Department of Physics, Columbia University, New York, New York 10027, USA.
Phys Rev Lett. 2023 Mar 17;130(11):113002. doi: 10.1103/PhysRevLett.130.113002.
We report on the creation of bosonic NaCs molecules in their absolute rovibrational ground state via stimulated Raman adiabatic passage. We create ultracold gases with up to 22 000 dipolar NaCs molecules at a temperature of 300(50) nK and a peak density of 1.0(4)×10^{12} cm^{-3}. We demonstrate comprehensive quantum state control by preparing the molecules in a specific electronic, vibrational, rotational, and hyperfine state. We measure the ground state ac polarizability at 1064 nm along with the two-body loss rate, which we find to be universal. Employing the tunability and strength of the permanent electric dipole moment of NaCs, we induce dipole moments of up to 2.6 D at a dc electric field of 2.1(2) kV/cm and demonstrate strong microwave coupling between the two lowest rotational states with a Rabi frequency of 2π×45 MHz. A large electric dipole moment, accessible at relatively small electric fields, makes ultracold gases of NaCs molecules well suited for the exploration of strongly interacting phases of dipolar quantum matter.
我们通过受激拉曼绝热通道报告了玻色子 NaCs 分子在其绝对转动和振动基态中的生成。我们在 300(50) nK 的温度和 1.0(4)×10^{12} cm^{-3}的峰值密度下，创造了多达 22000 个偶极子 NaCs 分子的超冷气体。我们通过将分子制备在特定的电子、振动、旋转和超精细状态中，证明了全面的量子态控制。我们沿着 1064nm 测量了基态 ac 极化率和双体损耗率，发现它们是通用的。利用 NaCs 的永久电偶极矩的可调谐性和强度，我们在 2.1(2) kV/cm 的直流电场中诱导了高达 2.6 D 的偶极矩，并演示了两个最低旋转态之间的强微波耦合，其 Rabi 频率为 2π×45 MHz。大的电偶极矩，在相对较小的电场下即可获得，使得 NaCs 分子的超冷气体非常适合探索强相互作用的偶极量子物质相。
