Built-up of Inverted Phonon Distribution in GaN

Brazis, R.; Raguotis, R.
April 2007
AIP Conference Proceedings;2007, Vol. 893 Issue 1, p149
Academic Journal
Phonon distribution built-up in high electric field in cubic n-type GaN is investigated using modified Monte Carlo method. The results show that LO-phonon band population grows by many orders of magnitude in time-scale less than two femtosecond upon stepwise switched electric field, and exhibits slower growth and decaying oscillations in subsequent several picoseconds before accessing stationary state. Under electron streaming conditions, LO phonon distribution in momentum space is inverted with respect to LA phonons, and the maximum LO phonon number is centered at the momentum value kLO corresponding to electron energy equaling to the LO phonon energy. © 2007 American Institute of Physics


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