Superposition states master equation

Since the driven and undriven transitions are coupled through the Tn terms, it is convenient to introduce symmetric and antisymmetric superposition states of the dressed states +, V) and 3, V). According to Eq. (68), the superposition states diagonalise the dissipative (damping) part of the master equation of the system. The superposition states can be written as [51]... 

Here, we discuss an alternative scheme where the superposition state <1>) can be generated in two identical atoms driven in free space by a coherent laser field. This can happen when the atoms are in nonequivalent positions in the driving field, where the atoms experience different intensities and phases of the driving field. The populations of the collective states of the system can be found from the master equation (31). We use the set of the collective states (35) as an appropriate representation for the density operator... 

Superposition techniques may also be used to correlate stress-strain behavior in the rubbery state. In their study of styrene-acrylonitrile copolymers filled with glass beads, Narkis and Nicolais (1971) obtained stress-strain curves at temperatures above 7. Stress-strain curves were plotted for different fractions of filler, and in terms of both the polymer and composite strain. At a given strain, the stress increased with increasing filler concentration, as expected. It was possible to shift curves of stress vs. polymer strain along the stress axis to produce a master curve (Figure 12.12). In addition to the empirical measurements, an attempt was made to calculate stress-strain curves from the strain-independent relaxation moduli (see Section 1.16 and Chapter 10) by integrating the following equation ... 

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