Discovery of atomic clock-like spin defects in simple oxides from first principles

Area of Science:

• Quantum computing
• Materials science
• Solid-state physics

Background:

• Simple oxides are promising hosts for solid-state spin qubits due to their low nuclear spin noise.
• However, suitable spin defects have not been identified in these materials.

Purpose of the Study:

• To predict and characterize novel spin defects in calcium oxide with potential for quantum information processing.
• To explore their electronic properties and suitability as qubit hosts.

Main Methods:

• High-throughput first-principles calculations were employed to screen potential spin defects.
• Electronic properties, zero-phonon lines, and many-body energy levels were computed.

Main Results:

• Predicted spin defects in calcium oxide, involving dopant atoms (Sb, Bi, I) and vacancies, show properties similar to the NV center in diamond.
• The bismuth complex exhibits emission in the telecommunication range and a viable optical cycle for qubit initialization.
• Defects with 209Bi dopants demonstrate atomic clock-like transitions with Hanh-echo coherence times exceeding seconds.

Conclusions:

• Novel spin defects in calcium oxide offer a promising platform for long-coherence-time quantum states.
• These findings advance the development of quantum technologies using simple oxide hosts.