Skip to main content
Log in

Quantum walks with an anisotropic coin I: spectral theory

  • Published:
Letters in Mathematical Physics Aims and scope Submit manuscript

Abstract

We perform the spectral analysis of the evolution operator U of quantum walks with an anisotropic coin, which include one-defect models, two-phase quantum walks, and topological phase quantum walks as special cases. In particular, we determine the essential spectrum of U, we show the existence of locally U-smooth operators, we prove the discreteness of the eigenvalues of U outside the thresholds, and we prove the absence of singular continuous spectrum for U. Our analysis is based on new commutator methods for unitary operators in a two-Hilbert spaces setting, which are of independent interest.

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. Aharonov, Y., Davidovich, L., Zagury, N.: Quantum random walks. Phys. Rev. A 48, 1687–1690 (1993)

    Article  ADS  Google Scholar 

  2. Ambainis, A., Bach, E., Nayak, A., Vishwanath, A., Watrous, J.: One-dimensional quantum walks. In: Proceedings of the Thirty-Third Annual ACM Symposium on Theory of Computing, pp. 37–49. ACM, New York (2001)

  3. Amrein, W.O., Boutet de Monvel, A., Georgescu, V.: \(C_0\)-Groups, Commutator Methods and Spectral Theory of \(N\)-Body Hamiltonians, vol. 135 of Progress in Mathematics. Birkhäuser Verlag, Basel (1996)

    Book  MATH  Google Scholar 

  4. Asch, J., Bourget, O., Joye, A.: Spectral stability of unitary network models. Rev. Math. Phys. 27(7), 1530004 (2015)

    Article  MathSciNet  MATH  Google Scholar 

  5. Astaburuaga, M.A., Bourget, O., Cortés, V.H.: Commutation relations for unitary operators I. J. Funct. Anal. 268(8), 2188–2230 (2015)

    Article  MathSciNet  MATH  Google Scholar 

  6. Astaburuaga, M.A., Bourget, O., Cortés, V.H.: Commutation relations for unitary operators II. J. Approx. Theory 199, 63–94 (2015)

    Article  MathSciNet  MATH  Google Scholar 

  7. Astaburuaga, M.A., Bourget, O., Cortés, V.H., Fernández, C.: Floquet operators without singular continuous spectrum. J. Funct. Anal. 238(2), 489–517 (2006)

    Article  MathSciNet  MATH  Google Scholar 

  8. Baumgärtel, H., Wollenberg, M.: Mathematical Scattering Theory, Volume 9 of Operator Theory: Advances and Applications. Birkhäuser Verlag, Basel (1983)

    Book  MATH  Google Scholar 

  9. Bourget, O., Howland, J., Joye, A.: Spectral analysis of unitary band matrices. Commun. Math. Phys. 234(2), 191–227 (2003)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  10. Cantero, M.J., Grünbaum, F.A., Moral, L., Velázquez, L.: One-dimensional quantum walks with one defect. Rev. Math. Phys. 24(2), 1250002 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  11. Cedzich, C., Grünbaum, F.A., Stahl, C., Velázquez, L., Werner, A.H., Werner, R.F.: Bulk-edge correspondence of one-dimensional quantum walks. J. Phys. A 49(21), 21LT01 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  12. Chandrashekar, C.M., Obuse, H., Busch, Th.: Entanglement Properties of Localized States in 1D Topological Quantum Walks. arXiv:1502.00436

  13. Endo, S., Endo, T., Konno, N., Segawa, E., Takei, M.: Limit theorems of a two-phase quantum walk with one defect. Quantum Inf. Comput. 15(15–16), 1373–1396 (2015)

    MathSciNet  Google Scholar 

  14. Endo, S., Endo, T., Konno, N., Segawa, E., Takei, M.: Weak limit theorem of a two-phase quantum walk with one defect. Interdiscip. Inf. Sci. 22(1), 17–29 (2016)

  15. Endo, T., Konno, N., Obuse, H.: Relation between two-phase quantum walks and the topological invariant. arXiv:1511.04230

  16. Fernández, C., Richard, S., Tiedra de Aldecoa, R.: Commutator methods for unitary operators. J. Spectr. Theory 3(3), 271–292 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  17. Fuda, T., Funakawa, D., Suzuki, A.: Weak limit theorem for a one-dimensional split-step quantum walk (in preparation)

  18. Fuda, T., Funakawa, D., Suzuki, A.: Localization for a one-dimensional split-step quantum walk with bound states robust against perturbations (in preparation)

  19. Gross, D., Nesme, V., Vogts, H., Werner, R.F.: Index theory of one dimensional quantum walks and cellular automata. Commun. Math. Phys. 310(2), 419–454 (2012)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  20. Grössing, G., Zelilinger, A.: Quantum cellular automata. Complex Syst. 2(2), 197–208 (1988)

    MathSciNet  MATH  Google Scholar 

  21. Gudder, S.P.: Quantum Probability. Probability and Mathematical Statistics. Academic Press Inc, Boston (1988)

    MATH  Google Scholar 

  22. Ichihara, A., Matsuoka, L., Segawa, E., Yokoyama, K.: Isotope-selective dissociation of diatomic molecules by terahertz optical pulses. Phys. Rev. A 91, 043404 (2015)

    Article  ADS  Google Scholar 

  23. Kitaev, A.: Anyons in an exactly solved model and beyond. Ann. Phys. 321(1), 2–111 (2006)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  24. Kitagawa, T.: Topological phenomena in quantum walks: elementary introduction to the physics of topological phases. Quantum Inf. Process. 11(5), 1107–1148 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  25. Kitagawa, T., Broome, M.A., Fedrizzi, A., Rudner, M.S., Berg, E., Kassal, I., Aspuru-Guzik, A., Demler, E., White, A.G.: Observation of topologically protected bound states in photonic quantum walks. Nat. Commun. 3, 882 (2012)

    Article  ADS  Google Scholar 

  26. Kitagawa, T., Rudner, M.S., Berg, E., Demler, E.: Exploring topological phases with quantum walks. Phys. Rev. A 82, 033429 (2010)

    Article  ADS  Google Scholar 

  27. Konno, N.: Quantum random walks in one dimension. Quantum Inf. Process. 1(5), 345–354 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  28. Konno, N.: A new type of limit theorems for the one-dimensional quantum random walk. J. Math. Soc. Jpn. 57(4), 1179–1195 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  29. Konno, N.: Localization of an inhomogeneous discrete-time quantum walk on the line. Quantum Inf. Process. 9(3), 405–418 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  30. Konno, N., Łuczak, T., Segawa, E.: Limit measures of inhomogeneous discrete-time quantum walks in one dimension. Quantum Inf. Process. 12(1), 33–53 (2013)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  31. Manouchehri, K., Wang, J.: Physical implementation of quantum walks. In: Quantum Science and Technology. Springer, Heidelberg (2014)

  32. Măntoiu, M.: \(C^*\)-algebras, dynamical systems at infinity and the essential spectrum of generalized Schrödinger operators. J. Reine Angew. Math. 550, 211–229 (2002)

    MathSciNet  MATH  Google Scholar 

  33. Meyer, D.A.: From quantum cellular automata to quantum lattice gases. J. Stat. Phys. 85(5–6), 551–574 (1996)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  34. Ohno, H.: Unitary equivalent classes of one-dimensional quantum walks. Quantum Inf. Process. 15(9), 3599–3617 (2016)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  35. Portugal, R.: Quantum walks and search algorithms. In: Quantum Science and Technology. Springer, New York (2013)

  36. Reed, M., Simon, B.: Methods of Modern Mathematical Physics II, Fourier Analysis, Self-Adjointness. Academic Press, New York (1975)

    MATH  Google Scholar 

  37. Richard, S., Suzuki, A., Tiedra de Aldecoa, R.: Quantum walks with an anisotropic coin II: scattering theory (in preparation)

  38. Richard, S., Tiedra de Aldecoa, R.: A few results on Mourre theory in a two-Hilbert spaces setting. Anal. Math. Phys. 3(2), 183–200 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  39. Richard, S., Tiedra de Aldecoa, R.: Spectral analysis and time-dependent scattering theory on manifolds with asymptotically cylindrical ends. Rev. Math. Phys. 25(2), 1350003 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  40. Ruzhansky, M., Turunen, V.: Pseudo-Differential Operators and Symmetries, Volume 2 of Pseudo-Differential Operators. Theory and Applications. Birkhäuser Verlag, Basel (2010) (Background analysis and advanced topics)

  41. Sahbani, J.: The conjugate operator method for locally regular Hamiltonians. J. Oper. Theory 38(2), 297–322 (1997)

    MathSciNet  MATH  Google Scholar 

  42. Segawa, E., Suzuki, A.: Generator of an abstract quantum walk. Quantum Stud. Math. Found. 3(1), 11–30 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  43. Suzuki, A.: Asymptotic velocity of a position-dependent quantum walk. Quantum Inf. Process. 15(1), 103–119 (2016)

    Article  MathSciNet  MATH  ADS  Google Scholar 

  44. Tiedra de Aldecoa, R.: Degree, mixing, and absolutely continuous spectrum of cocycles with values in compact lie groups. arXiv:1605.04198

  45. Venegas-Andraca, S.E.: Quantum walks: a comprehensive review. Quantum Inf. Process. 11(5), 1015–1106 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  46. Watrous, J.: Quantum simulations of classical random walks and undirected graph connectivity. J. Comput. System Sci. 62(2): 376–391 (2001). Special issue on the Fourteenth Annual IEEE Conference on Computational Complexity (Atlanta, GA, 1999)

  47. Weidmann, J.: Linear Operators in Hilbert Spaces, Volume 68 of Graduate Texts in Mathematics. Springer, New York (1980). Translated from the German by Joseph Szücs

  48. Wójcik, A., Łuczak, T., Kurzyński, P., Grudka, A., Gdala, T., Bednarska-Bzdęga, M.: Trapping a particle of a quantum walk on the line. Phys. Rev. A 85, 012329 (2012)

    Article  ADS  Google Scholar 

  49. Yafaev, D.R.: Mathematical Scattering Theory, Volume 105 of Translations of Mathematical Monographs. American Mathematical Society, Providence, RI (1992) General Theory. Translated from the Russian by J. R, Schulenberger

Download references

Acknowledgements

R. Tiedra de Aldecoa thanks the Graduate School of Mathematics of Nagoya University for its warm hospitality in January–February 2017. The authors also thank the anonymous referee for the valuable comments and for pointing out missing references which have been added.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to R. Tiedra de Aldecoa.

Additional information

S. Richard was supported by JSPS Grant-in-Aid for Young Scientists A no 26707005, and on leave of absence from Univ. Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5208, Institut Camille Jordan, 43 blvd. du 11 novembre 1918, F-69622 Villeurbanne cedex, France.

A. Suzuki was supported by JSPS Grant-in-Aid for Young Scientists B no 26800054.

R. Tiedra de Aldecoa was supported by the Chilean Fondecyt Grant 1170008.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Richard, S., Suzuki, A. & Tiedra de Aldecoa, R. Quantum walks with an anisotropic coin I: spectral theory. Lett Math Phys 108, 331–357 (2018). https://doi.org/10.1007/s11005-017-1008-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11005-017-1008-1

Keywords

Mathematics Subject Classification

Navigation