ABSTRACT
From the results discussed through the preceding chapter one
realizes that at a fundamental level, basic physical processes, like
interference effects, lasing action, quasi-phase matching conditions,
or the coupling between electromagnetic waves and the collective
motion of electrons, to name just a few, are essentially the same in
both periodic and aperiodic optical systems. Thus, in the theory of
aperiodic systems the role of order itself is what it is all about (at
least at the current state of knowledge in the field). Accordingly, we
shall open this chapter by considering three main queries:
(1) What can be done with photonic devices based on aperiodic
arrangements that cannot be done with periodic based ones?
