The Nature of the Electronic Excitations
Chapter
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Abstract
In this chapter we examine the nature of the electronic excitations stimulated during collision cascades. We find that these excitations are well-characterized by an elevated electronic pseudo-temperature and develop a simple temperature fitting algorithm. We explain the emergence of a pseudo-temperature despite the absence of thermalizing electron–electron interactions or a correct treatment of the electron–phonon interaction in our Ehrenfest dynamics by considering the spectrum of frequencies in the ionic motion in a typical cascade. Identifying an inconsistency between a rising electronic temperature and the fixed entropy of the electronic density matrix, we briefly consider an alternative definition of the electronic entropy.
Keywords
Density Matrix Ionic Motion Dirac Distribution Collision Cascade Occupation Distribution
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