Abstract
In order to study the vibrational properties of harmonic disordered solids we consider two models for disorder: Randomly fluctuating elastic constants (intrinsic disorder) and coupling to local oscillators (defects) with random eigen frequencies. The first model is treated in self-consistent Born approximation (SCBA), whereas the second can be solved exactly. This enables us to discuss the accuracy of the SCBA. In both models an enhancement of the low-frequency vibrational density of states over that predicted by Debye is obtained (”boson peak”) as a result of the presence of the disorder. In the frequency regime above the boson peak an almost exponential decrease of the reduced density of states is obtained, which is widely observed in experiments. Whereas the gross features of the models are similar, the details can be different, depending on the model parameters chosen.
It is argued that models involving intrinsic disorder are suitable for structurally disordered solids, whereas defect models seem more adequate for disordered crystals.
PACS number: 65.60.+a
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REFERENCES
S. Hunklinger and W. Arnold in Physical Acoustics, W. P. Mason and R. N. Thurston, Eds., Academic Press New York 1976, p. 155
W. A. Philips, (Hrsg.), Amorphous Solids–Low Temperature Properties, Springer, Berlin, 1981.
A. Wüger, Prom Coherent Tunneling to Relaxation, Springer Tracts in Modern Physics, 135, Springer, Heidelberg, 1997
Proceedings of the 10th International Conference on Phonon Scattering in Condensed Malter, Dartmouth College, Hanover, NH, 2001, Physica B & C 316-317
C. A. Angell, K. L. Ngai, G. B. McKenna, P.-F. McMillan, S. W. Martin, J. Appl. Phys. 88, 3113 (2000)
see e. g. M. Foret, R. Vacher, E. Courtens, G. Monaco, Phys. Rev. B, 66, 024204 (2002)
V. G. Karpov, M. T. Klinger, F. N. Ignatiev, Sov. Phys. JETP 57, 439 (1983); U. Buchenau et al. Phys. Rev. B 43, 5039 (1991); ibid., 46, 2798 (1992); V. L. Gurevich, D. A. Parshin, T, Pelons, H. R. Schober, Phys. Rev. B 48, 16318 (1993)
R. Kühn, D. Horstmann, Phys. Rev. Lett. 78, 4067 (1997)
W. Schirmacher, G. Diezemann, C. Ganter, Phys. Rev. Lett. 81, 136 (1998)
S. N. Taraskin, Y. H. Loh, G. Natarajan, S. R. Elliott, Phys. Rev. Lett. 86, 1255 (2001); S. N. Taraskin, S. R. Elliott in Ref.4
W. Götze, M. R. Mayr, Phys. Rev. E 61, 587 (2000)
T. W. Kantelhardt, S. Russ, A. Bunde, Phys. Rev. B 63, 064302 (2001)
T.S. Grigera, V. Martin-Mayor, G. Parisi, P. Verrocchio, Nature 422, 289 (2003).
W. Schirmacher, M. Pöhlmann, E. Maurer, phys. stat sol. (b) 230, 31 (2002)
W. Schirmacher, E. Maurer, M. Pöhlmann, phys. stat sol. (c) 1, 17 (2004)
A. I. Chumakov, I. Sergueev, U. van Bürck, W. Schirmacher, T. Asthalter, R. Rüffer, O. Leupold, W. Petry, Phys. Rev. Lett, in print
For further refs. on the boson peak see the reference lists of Refs. 6, 9 or the recent numerical investigation of amorphous silica by J. Horbach, W. Kob and K. Binder, Eur. PHys. J. B 19, 531 (2001)
S. John, II. Sompolinsky, and M. J. Stephen, Phys. Rev. B 27, 5592 (1983); S. John, and M. J. Stephen, Phys. Rev. B 28, 6358 (1983); M. J. Stephen in The Mathematics and Physics of Disordered Media, B. D. Hughes, and B. W. Ninham, Eds., Springer-Verlag Heidelberg 1983; S. John, Phys. Rev. B 31, 304 (1985)
M. V. Klein, Phys. Rev. 186, 839 (1969)
S. R. Elliott, Europhys. Lett. 19, 201 (1992)
F. Wegner, Z. Physik. B 35, 207 (1979): L. Schäfer, F. Wegner, ibid. 38, 113 (1980); see also McKane and M. Stone Ann. Phys. (New York), 131, 36 (1981)
S. F. Edwards, R. G. Jones, J. Phys. A: Math. Gen. 9, 1595 (1976)
J. L. van Hemmen, R. G. Palmer, J. Phys. Math. Gen. 4, 581 (1978)
E. N. Economou, Green's functions in Quantum Physics, Springer-Verlag Berlin 1983.
E. Maurer, Diploma Dissertation, TU München, 2002, unpublished
M. L. Mehta, Random Matrices and the Statistical Theory of Energy Levels, Academic Press, London and New York, 1967. The original derivation of the half-elliptic law is attributed
N. F. Mott and E. A. Davis, Electronic Processes in Noncrystalline Materials Clarendon, Oxford, 1979
E. Akkermans and R. Maynard, Phys. Rev. B 32, 7850 (1985)
A. Altland, 2004, private communication
W. Schirmacher, M. Wagener in Dynamics in Disordered Materials, D. Richter, A. J. Dianoux, W. Petry, J, Teixeira, Eds., Springer, Heidelberg, p. 231 (1989); Phil. Mag. B 65, 607 (1992), Solid State Communications 86, 597 (1993)
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Maurer, E., Schirmacher, W. Local Oscillators vs. Elastic Disorder: A Comparison of Two Models for the Boson Peak. Journal of Low Temperature Physics 137, 453–470 (2004). https://doi.org/10.1023/B:JOLT.0000049065.04709.3e
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DOI: https://doi.org/10.1023/B:JOLT.0000049065.04709.3e