Coherent Plasmon-Phonon Oscillations in a GaAs Schottky Barrier Sample

• Published in: physica status solidi (b) Vol. 204; no. 1; pp. 91 - 94
• Main Authors: van Hall, P. J., de Jong, W., van Etteger, A., Rasing, Th
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01-11-1997; WILEY‐VCH Verlag
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/1521-3951(199711)204:1<91::AID-PSSB91>3.0.CO;2-L

We have observed coherent plasmon–phonon oscillations in a biased GaAs–Au Schottky barrier sample excited by intense fs laser pulses using time resolved Second Harmonic Generation. The results are compared with Monte‐Carlo simulations. To account for the observed dependence of the frequency on the excitation density it was necessary to separate the electric field in two components: one due to the space charge and the other following from the lattice polarization. In this way a coupling between the plasmon and the LO phonons is obtained, which resulted in a nearly perfect description of the experimentally observed frequencies.