- Open Access
High-fidelity single-qubit quantum state tomography of electron- nuclear hybrid spin register in diamond using Rabi oscillations
Phys. Rev. Research 8, 023151 – Published 11 May, 2026
DOI: https://doi.org/10.1103/j1s1-w37c
Abstract
We report on a quantum state characterization method, which we call Rabi-based quantum state tomography (RQST), that we have validated on single-qubit quantum states, in particular on the electron and nuclear spins of a single nitrogen-vacancy (NV) center in diamond, demonstrating high fidelities. The difference of RQST with conventional tomography methods is in the implementation of rotation operators and construction of the density matrix from the measured datasets. We demonstrate efficient quantum state control of the electron spin at room temperature with an average fidelity of 0.995 over more than 40 measurements on different states on the Bloch sphere. Also, we apply the methodology to the dark NV nuclear spin state. The state is read via the electron spin using the C-NOT two-qubit entanglement gate and demonstrates fidelities of the same order.
Physics Subject Headings (PhySH)
Corrections
15 June, 2026
Correction: The omission of a support statement in the Acknowledgments has been fixed.
Article Text
Supplemental Material
References (27)
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