Alkaline-earth-like (AEL) atoms with two valence electrons and a nonzero nuclear spin can be excited to Rydberg state for quantum computing. Typical AEL ground states possess no hyperfine splitting, but unfortunately a GHz-scale splitting seems necessary for Rydberg excitation. Though strong magnetic fields can induce a GHz-scale splitting, weak fields are desirable to avoid noise in experiments. Here, we provide two solutions to this outstanding challenge with realistic data of well-studied AEL isotopes. In the first theory, the two nuclear spin qubit states ∣0〉 and ∣1〉 are excited to Rydberg states ∣r〉 with detuning Δ and 0, respectively, where a MHz-scale detuning Δ arises from a weak magnetic field on the order of 1 G. With a proper ratio between Δ and Ω, the qubit state ∣1〉 can be fully excited to the Rydberg state while ∣0〉 remains there. In the second theory, we show that by choosing appropriate intermediate states a two-photon Rydberg excitation can proceed with only one nuclear spin qubit state. The second theory is applicable whatever the magnitude of the magnetic field is. These theories bring a versatile means for quantum computation by combining the broad applicability of Rydberg blockade and the incomparable advantages of nuclear-spin quantum memory in two-electron neutral atoms.

具有两个价电子和一个非零核自旋的碱土类（AEL）原子可以被激发到Rydberg态进行量子计算。典型的AEL基态没有超精细分裂，但不幸的是，里德堡激发似乎需要GHz级分裂。尽管强磁场会引起GHz级分裂，但为了避免实验中的噪声，还是需要弱磁场。在这里，我们通过深入研究的AEL同位素的真实数据，为解决这一严峻挑战提供了两种解决方案。在第一个理论中，两个核自旋量子位态∣0〉和∣1〉被激发到里德堡态∣ r〉分别具有Δ和0的失谐，其中兆赫兹级的失谐Δ是由1 G量级的弱磁场引起的。在Δ和Ω之间具有适当的比率时，量子位状态∣1>可以完全激发到Rydberg状态，而∣0>保留在那里。在第二种理论中，我们表明，通过选择适当的中间态，双光子里德堡激发只能以一个核自旋量子位态进行。无论磁场大小如何，第二种理论都适用。这些理论结合了Rydberg封锁的广泛适用性和核自旋量子存储在两电子中性原子中无与伦比的优势，为量子计算提供了一种通用的方法。