Demonstration of Entanglement-Enhanced Phase Estimation in Solid
arXiv:1408.0480 · doi:10.1038/ncomms7726
Abstract
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 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.
9 pages including the supplementary material, 6 figures in main text plus 3 figures in supplementary material
References in corpus (9)
- Beating the Standard Quantum Limit with Four Entangled Photons
- High-fidelity projective readout of a solid-state spin quantum register
- Entanglement-free Heisenberg-limited phase estimation
- Dynamic polarization of single nuclear spins by optical pumping of NV color centers in diamond at room temperature
- Decoherence-protected quantum gates for a hybrid solid-state spin register
- Long Phase Coherence Time and Number Squeezing of two Bose-Einstein Condensates on an Atom Chip
- Detection and control of individual nuclear spins using a weakly coupled electron spin
- Strongly enhanced photon collection from diamond defect centres under micro-fabricated integrated solid immersion lenses
- Entanglement-enhanced measurement of a completely unknown phase