Analyzing the Rydberg-based omg architecture for $^{171}$Yb nuclear spins

Abstract

Neutral alkaline earth(-like) atoms have recently been employed in atomic arrays with individual readout, control, and high-fidelity Rydberg-mediated entanglement. This emerging platform offers a wide range of new quantum science applications that leverage the unique properties of such atoms: ultra-narrow optical "clock" transitions and isolated nuclear spins. Specifically, these properties offer an optical qubit (o) as well as ground (g) and metastable (m) nuclear spin qubits, all within a single atom. We consider experimentally realistic control of this omg architecture and its coupling to Rydberg states for entanglement generation, focusing specifically on ytterbium-171 ( 171 Yb) with nuclear spin I = 1/2. We analyze the S-series Rydberg states of 171 Yb, described by the three spin-1/2 constituents (two electrons and the nucleus). We confirm that the F = 3/2 manifold -a unique spin configuration -is well suited for entangling nuclear spin qubits. Further, we analyze the F = 1/2 series -described by two overlapping spin configurations -using a multichannel quantum defect theory. We study the multilevel dynamics of the nuclear spin states when driving the clock or Rydberg transition with Rabi frequency Ωc = 2π×200 kHz or ΩR = 2π×6 MHz, respectively, finding that a modest magnetic field (≈ 200 G) and feasible laser polarization intensity purity ( 0.99) are sufficient for gate fidelities exceeding 0.99.