Elementary excitations in Si, Ge, and diamond time reversal affected

THIN SOLID FILMS

卷:517

Article

Kunert, H. W.¹  Machatine, A. G. J.¹  Malherbe, J. B.¹  Barnas, J.²  Hoffmann, A.³  Wagner, M. R.³ 

[1] Univ Pretoria, Dept Phys, ZA-0002 Pretoria, South Africa

[2] Adam Mickiewicz Univ Poznan, Dept Phys, PL-61614 Poznan, Poland

[3] Tech Univ Berlin, Inst Festkorperphys, D-10623 Berlin, Germany

关键词: Time Reversal;    Space Groups;    Phonons;    Diamond Si Ge;    Selection Rules;   

DOI  :  10.1016/j.tsf.2008.08.035

来源: Elsevier

【 摘 要 】

The Space Symmetry and the Time Reversal Symmetry of vibrational modes in Si, Ge and diamond are investigated. Using Space Symmetry we have derived the Lattice Mode Representation. Reducing it onto phonon species we obtain the symmetry allowed phonons and their degeneracies. Using reality test for irreducible representations according to those the phonons are classified we determine which modes are Time Reversal affected. Comparison with experimental data obtained by neutron scattering is made. The effect of Time Reversal Symmetry on electrons in the conduction band and holes in the valence band as well as on excitons is briefly discussed. (C) 2008 Elsevier B.V. All rights reserved.

【 授权许可】

Free