My PhD thesis - Condensed Matter Theory - Imperial College London

Chapter 8
Applying the plasmon normal
mode theory to slab systems
In this chapter, the application of the techniques developed in chapter 7 to jellium
slab systems will be discussed. The first task is to establish the form of the plasmon
normal modes; this will be dealt with in section 8.1. In section 8.2, the equations
of chapter 7 will be applied to these modes, giving the plasmon contribution to
the ground-state wave functions. Because studying plasmons only gives information
about long-wavelength correlations, it is necessary to combine the plasmonic form
with knowledge of the correlation between electrons at short distances in order to
generate good trial wave functions; this is discussed in section 8.3, along with the
results of using this method.
8.1 Classical plasmons in slabs
The system to be considered is illustrated in figure 8.1. It consists of a metal slab of
width s, characterised by a simple non-absorptive frequency-dependent conductivity,
surrounded by vacuum.
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