Generation of Highly Controllable Ytterbium Atom Array A Hybrid System of Nuclear Spin and Optical Clock Qubits

Yuma Nakamura, "Generation of Highly Controllable Ytterbium Atom Array: A Hybrid System of Nuclear Spin and Optical Clock Qubits Towards Quantum Error Correction"
English | ISBN: 9819528356 | | pages | PDF | 9 MB
This book offers a comprehensive exploration of a novel hybrid quantum computing platform based on dual-isotope ytterbium atom arrays. It presents pioneering work toward fault-tolerant quantum computation using nuclear spin and optical clock qubits in a neutral-atom system. The central challenge addressed in this book is the implementation of quantum error correction (QEC) in neutral-atom architectures, particularly the need for mid-circuit measurements-reading out ancilla qubits without disturbing data qubits. To overcome this, the author develops a hybrid array composed of fermionic 171Yb (serving as nuclear spin data qubits) and bosonic 174Yb (serving as optical clock ancilla qubits). This innovative combination enables non-destructive state readout and low crosstalk between qubits, laying critical groundwork for QEC protocols. This book demonstrates efficient state initialization and coherent control of both types of qubits in large-scale tweezer arrays. Through precise manipulation and rearrangement techniques, a defect-free, dual-isotope array is constructed with high single-site fidelity and minimal dual occupancy. Crosstalk analysis reveals that 174Yb imaging light does not degrade the coherence of adjacent 171Yb nuclear spin qubits-an essential result for practical QEC. In parallel, the work reports the development of a high-power, narrow-linewidth ultraviolet laser at 325 nm to achieve coherent Rydberg excitation of ytterbium atoms. The laser system, which includes a Raman fiber amplifier and high-finesse cavity for noise suppression, enables MHz-order Rabi oscillations between metastable and Rydberg states. This achievement provides a path toward implementing high-fidelity two-qubit gates, a cornerstone of universal quantum computation. This book combines theoretical insights, advanced laser engineering, and precision atomic control to establish a scalable, neutral-atom-based quantum computing architecture. Its interdisciplinary approach makes it a valuable resource not only for physicists working in quantum optics and atomic physics but also for engineers and computer scientists interested in next-generation quantum technologies.