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Spectral Gaps of Dirac Operators Describing Graphene Quantum Dots

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Abstract

The two-dimensional Dirac operator describes low-energy excitations in graphene. Different choices for the boundary conditions give rise to qualitative differences in the spectrum of the resulting operator. For a family of boundary conditions, we find a lower bound to the spectral gap around zero, proportional to |Ω|−1/2, where \({\Omega } \subset \mathbb {R}^{2}\) is the bounded region where the Dirac operator acts. This family contains the so-called infinite mass and armchair cases used in the physics literature for the description of graphene quantum dots.

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References

  1. Akhmerov, A. R., Beenakker, C. W. J.: Boundary conditions for Dirac fermions on a terminated honeycomb lattice. Phys. Rev. B 77, 085423 (2008)

    Article  ADS  Google Scholar 

  2. Ammann, B., Bär, C.: Dirac eigenvalue estimates on surfaces. Math. Z. 240(2), 423–449 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  3. Bär, C.: Lower eigenvalue estimates for Dirac operators. Math. Ann. 293(1), 39–46 (1992)

    Article  MathSciNet  MATH  Google Scholar 

  4. Beneventano, C.G., Fialkovsky, I., Santangelo, E.M., Vassilevich, D.V.: Charge density and conductivity of disordered berry-mondragon graphene nanoribbons. Eur. Phys. J. B 87(3), 1–9 (2014)

    Article  MathSciNet  Google Scholar 

  5. Benguria, R., Fournais, S., Stockmeyer, E., Van Den Bosch, H.: Self–adjointness of Two-Dimensional Dirac operators in Domains, Annales Herin Poincaré (online first), doi:10.1007/s00023-017-0554-5

  6. Berry, M.V., Mondragon, R.J.: Neutrino billiards: time-reversal symmetry-breaking without magnetic fields. Proc. Roy. Soc. London Ser. A 412 (1842), 53–74 (1987)

    Article  ADS  MathSciNet  Google Scholar 

  7. Booß-Bavnbek, B., Wojciechowski, K.P.: Elliptic boundary problems for Dirac operators, Mathematics: Theory & Applications. Birkhäuser Boston, Inc., Boston, MA (1993)

    Book  MATH  Google Scholar 

  8. Brey, L., Fertig, H. A.: Electronic states of graphene nanoribbons studied with the dirac equation. Phys. Rev. B 73, 235411 (2006)

    Article  ADS  Google Scholar 

  9. Castro Neto, A.H., Guinea, F., Peres, N.M.R., Novoselov, K.S., Geim, A.K.: The electronic properties of graphene. Rev. Mod. Phys. 81, 109–162 (2009)

    Article  ADS  Google Scholar 

  10. Fefferman, C.L., Weinstein, M.I.: Honeycomb lattice potentials and Dirac points. J. Amer. Math. Soc. 25(4), 1169–1220 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  11. Folland, G.B.: Introduction to partial differential equations, 2nd edn. Princeton University Press, Princeton, NJ (1995)

    MATH  Google Scholar 

  12. Freitas, P., Siegl, P.: Spectra of graphene nanoribbons with armchair and zigzag boundary conditions. Rev. Math. Phys. 26(10), 1450018, 32 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  13. Friedrich, T. h.: Der erste Eigenwert des Dirac-Operators einer kompakten, Riemannschen Mannigfaltigkeit nichtnegativer Skalarkrümmung. Math. Nachr. 97, 117–146 (1980)

    Article  MathSciNet  MATH  Google Scholar 

  14. Giovannetti, G., Khomyakov, P. A., Brocks, G., Kelly, P. J., Van den Brink, J.: Substrate-induced band gap in graphene on hexagonal boron nitride: Ab initio density functional calculations. Phys. Rev. B 76, 073103 (2007)

  15. Hijazi, O., Montiel, S., Zhang, X.: Eigenvalues of the Dirac operator on manifolds with boundary. Comm. Math. Phys. 221(2), 255–265 (2001)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  16. McCann, E., Fal’ko, V.I.: Symmetry of boundary conditions of the dirac equation for electrons in carbon nanotubes. J. Phys.: Condens. Matter. 16(13), 2371 (2004)

    ADS  Google Scholar 

  17. Orlof, A., Ruseckas, J., Zozoulenko, I. V.: Effect of zigzag and armchair edges on the electronic transport in single-layer and bilayer graphene nanoribbons with defects. Phys. Rev. B 88, 125409 (2013)

    Article  ADS  Google Scholar 

  18. Ponomarenko, L.A., Schedin, F., Katsnelson, M.I., Yang, R., Hill, E.W., Novoselov, K.S., Geim, A.K.: Chaotic Dirac billiard in graphene quantum dots. Science 320(5874), 356–358 (2008)

    Article  ADS  Google Scholar 

  19. Raulot, S.: The Hijazi inequality on manifolds with boundary. J. Geom. Phys. 56, 2189–2202 (2006)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  20. Ritter, K.A., Lyding, J.W.: The influence of edge structure on the electronic properties of graphene quantum dots and nanoribbons. Nat. Mater., 235 (2009)

  21. Schmidt, K.M.: A remark on boundary value problems for the Dirac operator. Quart. J. Math. Oxford Ser. (2) 46(184), 509–516 (1995)

    Article  MathSciNet  MATH  Google Scholar 

  22. Stockmeyer, E., Vugalter, S.: Infinite mass boundary conditions for Dirac operators, Preprint (2016), arXiv:1603.09657

  23. Subramaniam, D., Libisch, F., Li, Y., Pauly, C., Geringer, V., Reiter, R., Mashoff, T., Liebmann, M., Burgdörfer, J., Busse, C., Michely, T., Mazzarello, R., Pratzer, M., Morgenstern, M.: Wave-function mapping of graphene quantum dots with soft confinement. Phys. Rev. Lett. 108, 046801 (2012)

    Article  ADS  Google Scholar 

  24. Wallace, P.R.: The band theory of graphite. Phys. Rev. 71(9), 622 (1947)

    Article  ADS  MATH  Google Scholar 

  25. Wurm, J., Rycerz, A., Adagideli, İ.ç., Wimmer, M., Richter, K., Baranger, H. U.: Symmetry classes in graphene quantum dots: Universal spectral statistics, weak localization, and conductance fluctuations. Phys. Rev. Lett. 102, 056806 (2009)

    Article  ADS  Google Scholar 

  26. Zheng, H., Wang, Z. F., Luo, T., Shi, Q. W., Chen, J.: Analytical study of electronic structure in armchair graphene nanoribbons. Phys. Rev. B 75, 165414 (2007)

    Article  ADS  Google Scholar 

  27. Zhou, S.Y., Gweon, G.-H., Fedorov, A.V., First, P.N., de Heer, W.A., Lee, D.-H., Guinea, F., Castro Neto, A.H., Lanzara, A.: Substrate-induced bandgap opening in epitaxial graphene. Nat. Mater., 770 (2007)

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Acknowledgments

This work has been supported by the Iniciativa Científica Milenio (Chile) through the Millenium Nucleus RC–120002 “Física Matemática”. R.B. has been supported by Fondecyt (Chile) Projects # 112–0836, # 114–1155 and # 116–0856. S.F. acknowledges partial support from a Sapere Aude grant from the Danish Councils for Independent Research, Grant number DFF–4181-00221. E.S has been partially funded by Fondecyt (Chile) project # 114–1008. H. VDB. acknowledges support from Conicyt (Chile) through CONICYT–PCHA/Doctorado Nacional/2014. This work was carried out while S.F. was invited professor at Pontificia Universidad Católica de Chile.

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Correspondence to Hanne Van Den Bosch.

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Benguria, R.D., Fournais, S., Stockmeyer, E. et al. Spectral Gaps of Dirac Operators Describing Graphene Quantum Dots. Math Phys Anal Geom 20, 11 (2017). https://doi.org/10.1007/s11040-017-9242-4

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