2014/08/31 by Gang‐Qin Liu, Gang-Qin Liu, Yu-Ran Zhang +6 · 39 citations
Earth and Planetary Sciences · Materials Science · Mathematics · Physics and Astronomy · #Condensed matter physics #Diamond #Diamond and Carbon-based Materials Research #Field (mathematics) #Force Microscopy Techniques and Applications #High-pressure geophysics and materials #Materials science #Mathematics #Metrology #Open quantum system #Phase (matter) #Physics #Quantum #Quantum discord #Quantum entanglement #Quantum mechanics #Quantum metrology #Quantum network #Quantum sensor #Quantum technology #Qubit #Spin (aerodynamics) #Square root #Statistical physics #Thermodynamics #Vacancy defect #quant-ph
paper · pdf · doi:10.1038/ncomms7726
published in Nature Communications 6(1), 6726 (Nature Portfolio) · 9 pages including the supplementary material, 6 figures in main text plus 3 figures in supplementary material
openalex publication_date 2015/04/02 · arxiv created 2015/04/08 · arxiv updated 2015/04/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Precise parameter estimation plays a central role in science and technology. The statistical error in estimation can be decreased by repeating measurement, leading to that the resultant uncertainty of the estimated parameter is proportional to the square root of the number of repetitions in accordance with the central limit theorem. Quantum parameter estimation, an emerging field of quantum technology, aims to use quantum resources to yield higher statistical precision than classical approaches. Here we report the first room-temperature implementation of entanglement-enhanced phase estimation in a solid-state system: the nitrogen-vacancy centre in pure diamond. We demonstrate a super-resolving phase measurement with two entangled qubits of different physical realizations: an nitrogen-vacancy centre electron spin and a proximal (13)C nuclear spin. The experimental data shows clearly the uncertainty reduction when entanglement resource is used, confirming the theoretical expectation. Our results represent an elemental demonstration of enhancement of quantum metrology against classical procedure.