Abstract

Quantum metrology plays a fundamental role in many scientific areas. However, the complexity of engineering entangled probes and the external noise raise technological barriers for realizing the expected precision of the to-be-estimated parameter with given resources. Here, we address this problem by introducing adjustable controls into the encoding process and then utilizing a hybrid quantum-classical approach to automatically optimize the controls online. Our scheme does not require any complex or intractable off-line design, and it can inherently correct certain unitary errors during the learning procedure. We also report the first experimental demonstration of this promising scheme for the task of finding optimal probes for frequency estimation on a nuclear magnetic resonance (NMR) processor. The proposed scheme paves the way to experimentally auto-search optimal protocol for improving the metrology precision.

Details

Title
Hybrid quantum-classical approach to enhanced quantum metrology
Author
Yang, Xiaodong 1 ; Chen, Xi 2 ; Li, Jun 3 ; Peng Xinhua 4 ; Laflamme, Raymond 5 

 University of Science and Technology of China, Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639) 
 University of Science and Technology of China, Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639); University of Waterloo, Institute for Quantum Computing and Department of Physics and Astronomy, Waterloo, Canada (GRID:grid.46078.3d) (ISNI:0000 0000 8644 1405) 
 Southern University of Science and Technology, Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Shenzhen, China (GRID:grid.263817.9); Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Quantum Science and Engineering, Shenzhen, China (GRID:grid.263817.9) 
 University of Science and Technology of China, Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639); University of Science and Technology of China, CAS Key Laboratory of Microscale Magnetic Resonance, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639); University of Science and Technology of China, Synergetic Innovation Center of Quantum Information and Quantum Physics, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639) 
 University of Waterloo, Institute for Quantum Computing and Department of Physics and Astronomy, Waterloo, Canada (GRID:grid.46078.3d) (ISNI:0000 0000 8644 1405); Perimeter Institute for Theoretical Physics, Waterloo, Canada (GRID:grid.420198.6) (ISNI:0000 0000 8658 0851); Canadian Institute for Advanced Research, Toronto, Canada (GRID:grid.440050.5) (ISNI:0000 0004 0408 2525) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2477093302
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.