Year: 2020
Type: article
Abstract: Quantum technologies exploit entanglement to enhance various tasks beyond their classical limits including computation, communication and measurements. Quantum metrology aims to increase the precision of a measured quantity that is estimated in the presence of statistical errors using entangled quantum states. We present a novel approach for finding (near) optimal states for metrology in the presence of noise, using variational techniques as a tool for efficiently searching the high-dimensional space of quantum states, which would be classically intractable. We comprehensively explore systems consisting of up to 9 qubits and find new highly entangled states that are not symmetric under permutations and non-trivially outperform previously known states up to a constant factor 2. We consider a range of environmental noise models; while passive quantum states cannot achieve a fundamentally superior scaling (as established by prior asymptotic results) we do observe a significant absolute quantum advantage. We finally outline a possible experimental setup for variational quantum metrology which can be implemented in near-term hardware.
Source: New Journal of Physics
Authors: Bálint Koczor, Suguru Endo, Tyson Jones, Yuichiro Matsuzaki, Simon C Benjamin
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,610
Funders: Ministry of Education, Culture, Sports, Science and Technology, Japan Student Services Organization, Horizon 2020 Framework Programme, Intelligence Advanced Research Projects Activity, Engineering and Physical Sciences Research Council, Japan Society for the Promotion of Science, Clarendon Fund, Army Research Office
OpenAlex ID: W2969241977