Usefulness of Quantum Entanglement for Enhancing Precision in Frequency Estimation (2405.06548v2)
Abstract: We investigate strategies for reaching the ultimate limit on the precision of frequency estimation when the number of probes used in each run of the experiment is fixed. That limit is set by the quantum Cram\'er-Rao bound (QCRB), which predicts that the use of maximally entangled probes enhances the estimation precision, when compared with the use of independent probes. However, the bound is only achievable if the statistical model used in the estimation remains identifiable throughout the procedure. This in turn sets different limits on the maximal sensing time used in each run of the estimation procedure, when entangled and independent probes are used. When those constraints are taken into account, one can show that, when the total number of probes and the total duration of the estimation process are counted as fixed resources, the use of entangled probes is, in fact, disadvantageous when compared with the use of independent probes. In order to counteract the limitations imposed on the sensing time by the requirement of identifiability of the statistical model, we propose a time-adaptive strategy, in which the sensing time is adequately increased at each step of the estimation process, calculate an attainable error bound for the strategy and discuss how to optimally choose its parameters in order to minimize that bound. We show that the proposed strategy leads to much better scaling of the estimation uncertainty with the total number of probes and the total sensing time than the traditional fixed-sensing-time strategy. We also show that, when the total number of probes and the total sensing time are counted as resources, independent probes and maximally entangled ones have now the same performance, in contrast to the non-adaptive strategy, where the use of independent is more advantageous than the use of maximally entangled ones.
- R. M. Godun, P. B. R. Nisbet-Jones, J. M. Jones, S. A. King, L. A. M. Johnson, H. S. Margolis, K. Szymaniec, S. N. Lea, K. Bongs, and P. Gill, “Frequency ratio of two optical clock transitions in yb+171superscriptsuperscriptyb171{}^{171}{\mathrm{yb}}^{+}start_FLOATSUPERSCRIPT 171 end_FLOATSUPERSCRIPT roman_yb start_POSTSUPERSCRIPT + end_POSTSUPERSCRIPT and constraints on the time variation of fundamental constants,” Phys. Rev. Lett. 113, 210801 (2014).
- A. Arvanitaki, J. Huang, and K. Van Tilburg, “Searching for dilaton dark matter with atomic clocks,” Phys. Rev. D 91, 015015 (2015).
- G. Barontini, L. Blackburn, V. Boyer, F. Butuc-Mayer, X. Calmet, J. R. Crespo López-Urrutia, E. A. Curtis, B. Darquié, J. Dunningham, et al., “Measuring the stability of fundamental constants with a network of clocks,” EPJ Quantum Technology 9 (2022), 10.1140/epjqt/s40507-022-00130-5.
- S. Danilin, A. V. Lebedev, A. Vepsäläinen, G. B. Lesovik, G. Blatter, and G. S. Paraoanu, “Quantum-enhanced magnetometry by phase estimation algorithms with a single artificial atom,” npj Quantum Information 4 (2018), 10.1038/s41534-018-0078-y.
- H. Dong, L. Xue, W. Luo, J. Ge, H. Liu, Z. Yuan, H. Zhang, and J. Zhu, “A high-accuracy and non-intermittent frequency measurement method for larmor signal of optically pumped cesium magnetometer,” Journal of Instrumentation 16, P06001 (2021).
- X. Wu, Z. Pagel, B. S. Malek, T. H. Nguyen, F. Zi, D. S. Scheirer, and H. Müller, “Gravity surveys using a mobile atom interferometer,” Science Advances 5 (2019), 10.1126/sciadv.aax0800.
- B. Stray, A. Lamb, A. Kaushik, J. Vovrosh, A. Rodgers, J. Winch, F. Hayati, D. Boddice, A. Stabrawa, et al., “Quantum sensing for gravity cartography,” Nature 602, 590 (2022).
- K. Macieszczak, M. Fraas, and R. Demkowicz-Dobrzański, “Bayesian quantum frequency estimation in presence of collective dephasing,” New Journal of Physics 16, 113002 (2014).
- C. Sanner, N. Huntemann, R. Lange, C. Tamm, E. Peik, M. S. Safronova, and S. G. Porsev, “Optical clock comparison for lorentz symmetry testing,” Nature 567, 204 (2019).
- I. S. Madjarov, A. Cooper, A. L. Shaw, J. P. Covey, V. Schkolnik, T. H. Yoon, J. R. Williams, and M. Endres, “An atomic-array optical clock with single-atom readout,” Phys. Rev. X 9, 041052 (2019).
- S. L. Braunstein and C. M. Caves, “Statistical distance and the geometry of quantum states,” Phys. Rev. Lett. 72, 3439 (1994).
- J. J. . Bollinger, W. M. Itano, D. J. Wineland, and D. J. Heinzen, “Optimal frequency measurements with maximally correlated states,” Phys. Rev. A 54, R4649 (1996).
- S. F. Huelga, C. Macchiavello, T. Pellizzari, A. K. Ekert, M. B. Plenio, and J. I. Cirac, “Improvement of frequency standards with quantum entanglement,” Phys. Rev. Lett. 79, 3865 (1997).
- D. Cohen, T. Gefen, L. Ortiz, and A. Retzker, “Achieving the ultimate precision limit with a weakly interacting quantum probe,” npj Quantum Information 6, 1 (2020).
- F. Toscano, W. P. Bastos, and R. L. de Matos Filho, “Attainability of the quantum information bound in pure-state models,” Phys. Rev. A 95, 042125 (2017).
- C. Bonato, M. S. Blok, H. T. Dinani, D. W. Berry, M. L. Markham, D. J. Twitchen, and R. Hanson, “Optimized quantum sensing with a single electron spin using real-time adaptive measurements,” Nature nanotechnology 11, 247 (2016).
- R. W. Keener, Theoretical Statistics: Topics for a Core Course, Springer Texts in Statistics (Springer New York, 2010).
- E. Lehmann and G. Casella, Theory of Point Estimation, Springer Texts in Statistics (Springer New York, 2006).
- B. M. Escher, R. L. de Matos Filho, and L. Davidovich, “Quantum metrology for noisy systems,” Brazilian Journal of Physics 41, 229 (2011).
- A. Fujiwara, “Strong consistency and asymptotic efficiency for adaptive quantum estimation problems,” Journal of Physics A: Mathematical and General 39, 12489 (2006).
- M. A. Rodríguez-García, I. P. Castillo, and P. Barberis-Blostein, “Efficient qubit phase estimation using adaptive measurements,” Quantum 5, 467 (2021).
- L. Pezzé and A. Smerzi, “Sub shot-noise interferometric phase sensitivity with beryllium ions schrödinger cat states,” Europhysics Letters 78, 30004 (2007).
- C. Oh and W. Son, “Sub shot-noise frequency estimation with bounded a priori knowledge,” Journal of Physics A: Mathematical and Theoretical 48, 045304 (2014).
- D. W. Berry, B. L. Higgins, S. D. Bartlett, M. W. Mitchell, G. J. Pryde, and H. M. Wiseman, “How to perform the most accurate possible phase measurements,” Phys. Rev. A 80, 052114 (2009).
- L. Paninski, “Asymptotic Theory of Information-Theoretic Experimental Design,” Neural Computation 17, 1480 (2005).
- S. Boixo and R. D. Somma, “Parameter estimation with mixed-state quantum computation,” Phys. Rev. A 77, 052320 (2008).
- Z. Huang, K. R. Motes, P. M. Anisimov, J. P. Dowling, and D. W. Berry, “Adaptive phase estimation with two-mode squeezed vacuum and parity measurement,” Phys. Rev. A 95, 053837 (2017).
- D. Berry and H. Wiseman, in Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Postconference Technical Digest (IEEE Cat. No.01CH37172) (2001) pp. 60–61.
- M. A. Rodríguez-García, M. T. DiMario, P. Barberis-Blostein, and F. E. Becerra, “Determination of the asymptotic limits of adaptive photon counting measurements for coherent-state optical phase estimation,” npj Quantum Information 8, 94 (2022).
- A. Holevo, Probabilistic and Statistical Aspects of Quantum Theory (Edizioni della Normale, 2011).
- C. W. Helstrom, “Quantum detection and estimation theory,” Journal of Statistical Physics 1, 231–252 (1969).
- R. Beneduci, “On the relationships between the moments of a povm and the generator of the von neumann algebra it generates,” International Journal of Theoretical Physics 50, 3724–3736 (2011).
- M. DeGroot and M. Schervish, Probability and Statistics, Pearson custom library (Pearson Education, 2013).
- G. Casella and R. Berger, Statistical Inference (Chapman and Hall/CRC, 2024).
- F. Chapeau-Blondeau, “Optimizing qubit phase estimation,” Physical Review A 94, 1 (2016).
- A. Holevo, “Covariant measurements and uncertainty relations,” Reports on Mathematical Physics 16, 385–400 (1979).
- L. S. Martin, W. P. Livingston, S. Hacohen-Gourgy, H. M. Wiseman, and I. Siddiqi, “Implementation of a canonical phase measurement with quantum feedback,” Nature Physics 16, 1046–1049 (2020).
- R. Okamoto, S. Oyama, K. Yamagata, A. Fujiwara, and S. Takeuchi, “Experimental demonstration of adaptive quantum state estimation for single photonic qubits,” Phys. Rev. A 96, 022124 (2017).