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Computing Phonon Dispersion using Fast Zero-Point Correlations of Conjugate Variables

Published online by Cambridge University Press:  13 March 2018

Anant Raj
Affiliation:
Department of Nuclear Engineering, North Carolina State University, Raleigh, NC27695, U.S.A.
Jacob Eapen*
Affiliation:
Department of Nuclear Engineering, North Carolina State University, Raleigh, NC27695, U.S.A.
*
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Abstract

Time correlations of dynamic variables in the reciprocal space offer a rich theoretical setting for computing the phonon dispersion curves, particularly for systems with marked anharmonic interactions. Present techniques primarily rely either on the equipartition of energy between the phonon modes or on the oscillation of the time correlation of the normal mode projections. The former can lead to numerical errors due to deviation from equipartition while the latter usually requires long simulations for computing the time correlations. We investigate a different approach using the ratio of the normal mode expectation value of two conjugate variables – velocity and acceleration. Since only the correlations at the initial time (t=0) are needed, this approach is computationally attractive. In this work, we employ this method to extract the full Brillouin zone phonon dispersion for graphene.

Type
Articles
Copyright
Copyright © Materials Research Society 2018 

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References

REFERENCES

Pop, E., Nano Research 3 (3), 147-169 (2010).Google Scholar
Dhar, A., Advances in Physics 57 (5), 457-537 (2008).Google Scholar
Lepri, S., Livi, R., and Politi, A., Physics Reports 377 (1), 1-80 (2003).Google Scholar
Geim, A.K. and Novoselov, K.S., Nat Mater 6 (3), 183-191 (2007).Google Scholar
Iijima, S., Nature 354 (6348), 56-58 (1991).Google Scholar
Balandin, A.A., Nat Mater 10 (8), 569-581 (2011).CrossRefGoogle Scholar
Balandin, A.A., Ghosh, S., Bao, W., Calizo, I., Teweldebrhan, D., Miao, F., and Lau, C.N., Nano Letters 8 (3), 902-907 (2008).Google Scholar
Kresse, G., Furthmüller, J., and Hafner, J., EPL (Europhysics Letters) 32 (9), 729 (1995).Google Scholar
Dove, M.T., Introduction to lattice dynamics. (Cambridge university press, 1993) p. 179.Google Scholar
Kong, L.T., Computer Physics Communications 182 (10), 2201-2207 (2011).Google Scholar
Ladd, A.J.C., Moran, B., and Hoover, W.G., Physical Review B 34 (8), 5058-5064 (1986).Google Scholar
Thomas, J.A., Turney, J.E., Iutzi, R.M., Amon, C.H., and McGaughey, A.J.H., Physical Review B 81 (8), 081411 (2010).Google Scholar
Raj, A., PhD. Thesis, North Carolina State University, 2017.Google Scholar
Tersoff, J., Physical Review B 37 (12), 6991-7000 (1988).Google Scholar
Lindsay, L. and Broido, D.A., Physical Review B 81 (20), 205441 (2010).Google Scholar