Skip to main content
Log in

Zero measure spectrum for the almost Mathieu operator

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

Abstract

We study the almost Mathieu operator: (H α, λ, θ u)(n)=u(n+1)+u(n-1)+λ cos (2παn+θ)u(n), onl 2 (Z), and show that for all λ,θ, and (Lebesgue) a.e. α, the Lebesgue measure of its spectrum is precisely |4–2|λ‖. In particular, for |λ|=2 the spectrum is a zero measure cantor set. Moreover, for a large set of irrational α's (and |λ|=2) we show that the Hausdorff dimension of the spectrum is smaller than or equal to 1/2.

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. Aubry, S., Andre, G.: Analyticity breaking and Anderson localization in incommensurate lattices. Ann. Israel Phys. Soc.3, 133–164 (1980)

    Google Scholar 

  2. Avron, J., Simon, B.: Almost periodic Schrödinger operators. II. The integrated density of states. Duke Math. J.50, 369–391 (1983)

    Google Scholar 

  3. Avron, J., van Mouche, P., Simon, B.: On the measure of the spectrum for the almost Mathieu operator. Commun. Math. Phys.132, 103–118 (1990)

    Google Scholar 

  4. Bellissard, J., Lima, R., Testard, D.: A metal-insulator transition for the almost Mathieu model. Commun. Math. Phys.88, 207–234 (1983)

    Google Scholar 

  5. Bellissard, J., Simon, B.: Cantor spectrum for the almost Mathieu equation. J. Funct. Anal.48, 408–419 (1982)

    Google Scholar 

  6. Chambers, W.: Linear network model for magnetic breakdown in two dimensions. Phys. Rev. A140, 135–143 (1965)

    Google Scholar 

  7. Choi, M.D., Elliott, G.A., Yui, N.: Gauss polynomials and the rotation algebra. Invent. Math.99, 225–246 (1990)

    Google Scholar 

  8. Chulaevsky, V., Delyon, F.: Purely absolutely continuous spectrum for almost Mathieu operators. J. Stat. Phys.55, 1279–1284 (1989)

    Google Scholar 

  9. Cycon, H.L., Froese, R.G., Kirsch, W., Simon, B.: Schrödinger operators. Berlin, Heidelberg, New York: Springer 1987

    Google Scholar 

  10. Delyon, F.: Absence of localization for the almost Mathieu equation. J. Phys. A20, L21-L23 (1987)

    Google Scholar 

  11. Harper, P.G.: Single band motion of conduction electrons in a uniform magnetic field. Proc. Phys. Soc. Lond. A68, 874–892 (1955)

    Google Scholar 

  12. Helffer, B., Sjostrand, J.: Semi-classical analysis for Harper's equation. III. Cantor structure of the spectrum. Mém. Soc. Math. France (N.S.)39, 1–139 (1989)

    Google Scholar 

  13. Hofstadter, D.R.: Energy levels and wave functions of Bloch electrons in a rational or irrational magnetic field. Phys. Rev. B14, 2239–2249 (1976)

    Google Scholar 

  14. Falconer, K.J.: The geometry of fractal sets. Cambridge: Cambridge University Press 1985

    Google Scholar 

  15. Fröhlich, J., Spencer, T., Wittwer, P.: Localization for a class of one dimensional quasi-periodic Schrödinger operators. Commun. Math. Phys.132, 5–25 (1990)

    Google Scholar 

  16. Hardy, G.H., Wright, E.M.: An introduction to the theory of numbers, Fifth ed. Oxford: Oxford University Press, 1979

    Google Scholar 

  17. Last, Y.: A relation between a.c. spectrum of ergodic Jacobi matrices and the spectra of periodic approximants. Commun. Math. Phys.151, 183–192 (1993)

    Google Scholar 

  18. Last, Y., Wilkinson, M.: A sum rule for the dispersion relations of the rational Harper's equation. J. Phys. A25, 6123–6133 (1992)

    Google Scholar 

  19. Simon, B.: Almost periodic Schrödinger operators: a review. Adv. Appl. Math.3, 463–490 (1982)

    Google Scholar 

  20. Sinai, Ya.G.: Anderson localization for one-dimensional difference Schrödinger operator with quasiperiodic potential. J. Stat. Phys.46, 861–909 (1987)

    Google Scholar 

  21. Thouless, D.J.: Bandwidth for a quasiperiodic tight binding model. Phys. Rev. B28, 4272–4276 (1983)

    Google Scholar 

  22. Thouless, D.J.: Scaling for the discrete Mathieu equation. Commun. Math. Phys.127, 187–193 (1990)

    Google Scholar 

  23. Thouless, D.J., Tan, Y.: Total bandwidth for the Harper equation. III. Corrections to scaling. J. Phys. A24, 4055–4066 (1991)

    Google Scholar 

  24. Thouless, D.J., Tan, Y.: Scaling, localization and bandwidths for equations with competing periods. Physica A177, 567–577 (1991)

    Google Scholar 

  25. Toda, M.: Theory of nonlinear lattices, 2nd Ed., Chap. 4. Berlin, Heidelberg, New York: Springer 1989

    Google Scholar 

  26. Watson, G.I.: WKB analysis of energy band structure of modulated systems. J. Phys. A24, 4999–5010 (1991)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

Communicated by T. Spencer

Work partially supported by the GIF

Rights and permissions

Reprints and permissions

About this article

Cite this article

Last, Y. Zero measure spectrum for the almost Mathieu operator. Commun.Math. Phys. 164, 421–432 (1994). https://doi.org/10.1007/BF02101708

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02101708

Keywords

Navigation