Skip to main content
Log in

Gram Matrices of Mixed-State Ensembles

  • Published:
International Journal of Theoretical Physics Aims and scope Submit manuscript

Abstract

Gram matrices arise naturally in the consideration of pair-wise overlap of a family of vectors or quantum pure states, and play an important role in synthesizing information of a family of pure states. Since a quantum ensemble in general consists of mixed states, it is desirable to extend the concept of Gram matrix to the case of mixed states. By employing two prominent notions of overlap between mixed states, i.e., quantum affinity and quantum fidelity, one can readily extend the concept of Gram matrices of pure-state ensembles to that of mixed-state ensembles. We study these two extended versions of Gram matrices and reveal their fundamental properties. It is remarkable that while Gram matrix based on quantum affinity is non-negative definite (and thus can be regarded as a quantum state in a fictious system), the one based on quantum fidelity may fail to be non-negative definite. As applications of Gram matrices of mixed-state ensembles, we introduce two quantifiers of quantumness of ensembles via coherence of the corresponding Gram matrices, investigate their properties, and illustrate them in the qubit case.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Horn, R.A., Johnson, C.R.: Matrix Analysis. Cambridge Univeraity Press, Cambridge (1985)

    Book  MATH  Google Scholar 

  2. Fannes, M., Spincemaille, P.: The mutual affinity of random measures. arXiv:math-ph/0112034 (2001)

  3. De Cock, M.: Chaos and Gram’s matrix. AIP Conf. Proc. 553, 185 (2001)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  4. Banica, T., Curran, S.: Decomposition results for Gram matrix determinants. J. Math. Phys. 51, 113503 (2010)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  5. Fannes, M., De Melo, F., Roga, W.: Matrices of fidelities for ensembles of quantum states and the Holevo quantity. Quantum Inf. Comput. 12, 472 (2012)

    MathSciNet  MATH  Google Scholar 

  6. Mitchison, G., Jozsa, R.: Towards a geometrical interpretation of quantum-information compression. Phys. Rev. A 69, 032304 (2004)

    Article  ADS  MathSciNet  Google Scholar 

  7. Haikin, M., Zamir, R., Gavish, M.: Frame moments and Welch bound with erasures. arXiv:1801.04548 (2018)

  8. Robertson, H.P.: An indeterminacy relation for several observables and its classical interpretation. Phys. Rev. 46, 794 (1934)

    Article  ADS  MATH  Google Scholar 

  9. Gibilisco, P., Imparato, D., Isola, T.: A volume inequality for quantum Fisher information and the uncertainty principle. J. Stat. Phys. 130, 545 (2007)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  10. Bong, K. -W., Tischler, N., Patel, R.B., Wollmann, S., Pryde, G.J., Hall, M.J.W.: Strong unitary and overlap uncertainty relations: theory and experiment. Phys. Rev. Lett. 120, 230402 (2018)

    Article  ADS  Google Scholar 

  11. De Cock, M., Fannes, M., Spincemaille, P.: Quantum dynamics and Gram’s matrix. Euro. Phys. Lett. 49, 403 (2000)

    Article  ADS  MathSciNet  Google Scholar 

  12. Weigert, S.: The Gram matrix of a PT-symmetric quantum system. Czech. J. Phys. 54, 147 (2004)

    Article  ADS  MathSciNet  Google Scholar 

  13. Dieks, D.: Overlap and distinguishability of quantum states. Phys. Lett. A 126, 303 (1988)

    Article  ADS  MathSciNet  Google Scholar 

  14. Fuchs, C.A.: Distinguishability and accessible information in quantum theory. arXiv:9601020 (1996)

  15. Jozsa, R., Schlienz, J.: Distinguishability of states and von Neumann entropy. Phys. Rev. A 62, 012301 (2000)

    Article  ADS  MathSciNet  Google Scholar 

  16. Montanaro, A.: On the distinguishability of random quantum states. Commun. Math. Phys. 273, 619 (2007)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  17. Pozza, N.D., Pierobon, G.: Optimality of square-root measurements in quantum state discrimination. Phys. Rev. A 91, 042334 (2015)

    Article  ADS  Google Scholar 

  18. Vargas, E.M., Mun̈oz-Tapia, R.: Certified answers for ordered quantum discrimination problems. Phys. Rev. A 100, 042331 (2019)

    Article  ADS  Google Scholar 

  19. Cariolaro, G., Vigato, A.: Helstrom’s theory on quantum binary decision revisited. Inf. Th. Workshop IEEE 6, 242 (2010)

    Google Scholar 

  20. Duan, L. -M., Guo, G. -C.: Probabilistic cloning and identification of linearly independent quantum states. Phys. Rev. Lett. 80, 4999 (1998)

    Article  ADS  Google Scholar 

  21. Chefles, A.: Deterministic quantum state transformations. Phys. Lett. A 270, 14 (2000)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  22. Chefles, A., Jozsa, R., Winter, A.: On the existence of physical transformations between sets of quantum states. Int. J. Quantum Inf. 2, 11 (2004)

    Article  MATH  Google Scholar 

  23. Tay, B.A., Zainuddin, H.: Orbit classification of qutrit via the Gram matrix. Chinese Phys. Lett. 25, 1923 (2008)

    Article  ADS  Google Scholar 

  24. Stark, C.: Self-consistent tomography of the state-measurement Gram matrix. Phys. Rev. A 89, 052109 (2014)

    Article  ADS  Google Scholar 

  25. Sentís, G., Bagan, E., Calsamiglia, J., Chiribella, G., Mun̈oz-Tapia, R.: Quantum change point. Phys. Rev. Lett. 117, 150502 (2016)

    Article  ADS  Google Scholar 

  26. Zanardi, P., Styliaris, G., Venuti, L.C.: Measures of coherence-generating power for quantum unital operations. Phys. Rev. A 95, 052307 (2017)

    Article  ADS  Google Scholar 

  27. Chang, L., Luo, S., Sun, Y.: Superposition quantification. Commun. Theor. Phys. 68, 565 (2017)

    Article  ADS  MATH  Google Scholar 

  28. Li, N., Luo, S., Mao, Y.: Quantumness-generating capability of quantum dynamics. Quantum Inf. Process. 17, 74 (2018)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  29. Chen, L., Zhu, H., Wei, T.-C.: Connections of geometric measure of entanglement of pure symmetric states to quantum state estimation. Phys. Rev. A 83, 012305 (2011)

    Article  ADS  Google Scholar 

  30. Killoran, N., Steinhoff, F.E.S., Plenio, M.B.: Converting nonclassicality into entanglement. Phys. Rev. Lett. 116, 080402 (2016)

    Article  ADS  Google Scholar 

  31. Luo, S., Zhang, Q.: Informational distance on quantum-state space. Phys. Rev. A 69, 032106 (2004)

    Article  ADS  MathSciNet  Google Scholar 

  32. Fuchs, C.A.: Just two nonorthogonal quantum states. arXiv:quant-ph/9810032v1 (1998)

  33. Fuchs, C.A., Sasaki, M.: The quantumness of a set of quantum states. arXiv:quant-ph/0302108v1 (2003)

  34. Fuchs, C.A., Sasaki, M.: Squeezing quantum information through a classical channel: measuring the quantumness of a set of quantum states. Quantum Inf. Comput. 3, 377 (2003)

    MathSciNet  MATH  Google Scholar 

  35. Fuchs, C.A.: On the quantumness of a Hilbert space. Quantum Inf. Comput. 4, 467 (2004)

    MathSciNet  MATH  Google Scholar 

  36. Luo, S., Li, N., Cao, X.: Relative entropy between quantum ensembles. Period. Math. Hung. 59, 223 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  37. Luo, S., Li, N., Sun, W.: How quantum is a quantum ensemble. Quantum Inf. Process. 9, 711 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  38. Luo, S., Li, N., Fu, S.: Quantumness of quantum ensembles. Theor. Math. Phys. 169, 1724 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  39. Li, N., Luo, S., Mao, Y.: Quantifying the quantumness of ensembles. Phys. Rev. A 96, 022132 (2017)

    Article  ADS  Google Scholar 

  40. Qi, X., Gao, T., Yan, F.: Quantifying the quantumness of ensembles via unitary similarity invariant norms. Front. Phys. 13, 130309 (2018)

    Article  Google Scholar 

  41. Li, N., Luo, S., Song, H.: Monotonicity of quantumness of ensembles under commutativity-preserving channels. Phys. Rev. A 99, 052114 (2019)

    Article  ADS  Google Scholar 

  42. Mao, Y., Song, H.: Quantumness of ensembles via coherence. Phys. Lett. A 383, 2698 (2019)

    Article  ADS  MathSciNet  Google Scholar 

  43. Huang, H., Wu, Z., Zhu, C., Fei, S.-M.: Quantifying the quantumness of ensembles via generalized α-z-relative Rényi entropy. Int. J. Theor. Phys. 1 (2020)

  44. Bennett, C.H., Brassard, G.: Quantum cryptography: public-key distribution and tossing. In: Proceedings of IEEE International Conf. Computer, Systems, and Signal Processing, Bangalore, India (1984)

  45. Nielsen, M.A., Chuang, I.L.: Quantum Computation and Quantum Information. Cambridge University Press, Cambridge (2000)

    MATH  Google Scholar 

  46. Schumacher, B.: Sending entanglement through noisy quantum channels. Phys. Rev. A 54, 2614 (1996)

    Article  ADS  Google Scholar 

  47. Banaszek, K.: Fidelity balance in quantum operations. Phys. Rev. Lett. 86, 1366 (2001)

    Article  ADS  Google Scholar 

  48. Zanardi, P., Lidar, D.A.: Purity and state fidelity of quantum channels. Phys. Rev. A 70, 012315 (2004)

    Article  ADS  Google Scholar 

  49. Bahder, T.B., Lopata, P.A.: Fidelity of quantum interferometers. Phys. Rev. A 74(R), 051801 (2006)

    Article  ADS  Google Scholar 

  50. Simon, D.S., Sergienko, A.V., Bahder, T.B.: Dispersion and fidelity in quantum interferometry. Phys. Rev. A 78, 053829 (2008)

    Article  ADS  Google Scholar 

  51. Madsen, L.B., Mølmer, K.: Fidelities for transformations of unknown quantum states. Phys. Rev. A 73, 032342 (2006)

    Article  ADS  MathSciNet  Google Scholar 

  52. Quan, H.T., Cucchietti, F.M.: Quantum fidelity and thermal phase transitions. Phys. Rev. E 79, 031101 (2009)

    Article  ADS  MathSciNet  Google Scholar 

  53. Shao, L. -H., Xi, Z., Fan, H., Li, Y.: Fidelity and trace-norm distances for quantifying coherence. Phys. Rev. A 91, 042120 (2015)

    Article  ADS  Google Scholar 

  54. Xiong, C., Kumar, A., Huang, M., Das, S., Sen, U., Wu, J.: Partial coherence and quantum correlation with fidelity and affinity distances. Phys. Rev. A 99, 032305 (2019)

    Article  ADS  Google Scholar 

  55. Wu, X., You, B., Zhou, T.: Averaged fidelity-based steering criteria. Phys. Rev. A 103, 012212 (2021)

    Article  ADS  MathSciNet  Google Scholar 

  56. Baumgratz, T., Cramer, M., Plenio, M.B.: Quantifying coherence. Phys. Rev. Lett. 113, 140401 (2014)

    Article  ADS  Google Scholar 

  57. Yu, C.: Quantum coherence via skew information and its polygamy. Phys. Rev. A 95, 042337 (2017)

    Article  ADS  Google Scholar 

  58. Luo, S., Sun, Y.: Partial coherence with application to the monotonicity problem of coherence involving skew information. Phys. Rev. A 96, 022136 (2017)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Key R&D Program of China, Grant No. 2020YFA0712700, the National Natural Science Foundation of China, Grant Nos. 11875317, 12005104, and 61833010, and the Natural Science Foundation of the Jiangsu Higher Education Institutions of China, Grant No. 20KJB140028.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Shunlong Luo.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Sun, Y., Luo, S. & Lei, X. Gram Matrices of Mixed-State Ensembles. Int J Theor Phys 60, 3211–3224 (2021). https://doi.org/10.1007/s10773-021-04908-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10773-021-04908-8

Keywords

Navigation