Nuclear-Spin Neutral-Atom Qubit

Description

Nuclear-spin neutral-atom qubits encode logical states in long-lived nuclear spin manifolds (often in alkaline-earth(-like) atoms such as Sr/Yb), exploiting reduced magnetic sensitivity and ultra-narrow optical transitions.

Figure

Hamiltonian

Effective two-level encoding with weak magnetic sensitivity:

$H=\frac{{\omega }_0}{2}{\sigma }_z+\frac{\Omega (t)}{2}{\sigma }_x+\delta (t)\frac{1-{\sigma }_z}{2}$

with design target $\partial {\omega }_0/\partial B\approx 0$ at operating points.

Motivation

Nuclear-spin encodings are a coherence-first strategy for neutral-atom computing. By pushing logical storage into weakly magnetically sensitive manifolds, these architectures can extend memory lifetimes while still using excited-state manifolds (Rydberg or optical-clock transitions) for fast entanglement and control.

Key Findings

• Nuclear-spin manifolds support long-lived storage and robust idle behavior.
• Architectures can separate “memory” and “interaction” states to reduce crosstalk.
• Compatible with both tweezer and lattice implementations.
• Promising route for modular networked neutral-atom processors.

Key Metrics

Metric	Value	Notes	Fidelity reference
Coherence potential	very long (clock-state limited)	primary motivation	—
Gate strategy	Raman / optical-clock transitions	platform dependent	—
Entangling mechanism	Rydberg or cavity-mediated	architecture dependent	—
Main challenge	balancing coherence and gate speed	open optimization frontier	—

Linked Papers

• ma-2022-nuclear-spin-atom

Related Entries

• alkaline-earth-neutral-atom-clock-qubit
• rydberg-neutral-atom-qubit