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Electrons and Phonons in amorphous Si: Deformation Potentials and Solutions of the Time Dependent Schrödinger Equation

Published online by Cambridge University Press:  01 February 2011

D. A. Drabold
Affiliation:
Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, U.S.A.
Jun Li
Affiliation:
Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, U.S.A.
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Abstract

We employ first principles methods to explore the coupling between electrons and the lattice in amorphous silicon (a-Si). First we compute the adiabatic electronic response to phonon modes in a realistic model of a-Si. Then, we present a simulation of the electron dynamics of localized edge states in a-Si at room temperature by integrating the time dependent Schrödinger equation. We study the character of the spatial and spectral diffusion of the localized states and directly simulate and reveal the nature of thermally driven hopping. Phonon-induced resonant mixing leads to rapid electronic diffusion if states are available nearby in energy and real-space. We believe that many of the results we obtain are central to modeling transport involving localized states.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

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References

1. Anderson, P. W., Phys. Rev. 109, 1492 (1958).10.1103/PhysRev.109.1492Google Scholar
2.For an example of recent work on quantum transport see, Demkov, A., Zhang, X. and Drabold, D. A., Phys. Rev. B 64, 125306 (2001), and references therein.Google Scholar
3. Thomas, P., “Electronic transport in disordered Semiconductors” in Insulating and semiconducting glasses, ed. Boolchand, P., (World Scientific, Singapore 2000), p. 553.Google Scholar
4. Drabold, D. A., Fedders, P. A., Klemm, Stefan and Sankey, O. F., Phys. Rev. Lett. 67, 2179 (1991); D. A. Drabold and P. A. Fedders, Phys. Rev. B 60, R721, (1999); D. A. Drabold, J. Non.-Cryst. Sol. 266, 211 (2000).10.1103/PhysRevLett.67.2179Google Scholar
5. Djordjevic, B. R. et al., Phys. Rev. B, 52, 5685 (1995); F. Wooten and D. Weaire, Solid State Physics, edited by H. Ehrenreich and D. Turnbull (Academic Press, New York, 1991), Vol. 40, p.210.1103/PhysRevB.52.5685Google Scholar
6. Fedders, P. A., Drabold, D. A. and Nakhmanson, S. N., Phys. Rev. B 58, 15624 (1998).10.1103/PhysRevB.58.15624Google Scholar
7. Demkov, A., Ortega, J., Sankey, O. F., and Grumbach, M., Phys. Rev. B 52, 1618 (1995).Google Scholar
8. Aljishi, S., Cohen, J. D., Jin, S., and Ley, L., Phys. Rev. Lett. 64, 2811 (1990).10.1103/PhysRevLett.64.2811Google Scholar
9. Cobb, M. and Drabold, D. A., Phys. Rev. B 56, 3054 (1997).10.1103/PhysRevB.56.3054Google Scholar
10. Drabold, D. A. in Properties and Applications of Amorphous Materials, ed. by Thorpe, M. F. and Tichy, L., (Kluwer, Dordrecht, 2001).Google Scholar
11. Garcia, L., Numerical Methods for Physics, (Prentice Hall, 1994) Chap.8, pp. 244246.Google Scholar
12. Tomfohr, J. K. and Sankey, O. F., Phys. Stat. Sol. 226, 115 (2001).10.1002/1521-3951(200107)226:1<115::AID-PSSB115>3.0.CO;2-53.0.CO;2-5>Google Scholar
13. Mott, N. F. and Davis, E. A., Electronic Processes in Non-Crystalline Materials, 2nd. edition (Clarendon, Oxford, 1979).Google Scholar
14. Löwdin, P. O., Adv. Quantum Chem. 5, 185 (1970).10.1016/S0065-3276(08)60339-1Google Scholar
15.http://www.phy.ohiou.edu/~drabold; See also Li, J. and Drabold, D. A., Phys. Stat. Sol. (in press).Google Scholar
16. Dong, Jianjun and Drabold, D. A., Phys. Rev. Lett. 80, 1928 (1998).10.1103/PhysRevLett.80.1928Google Scholar