WEAK FIELD NONLINEAR OPTICAL-RESPONSE OF FERMIONS IN FRENKEL EXCITON CHAINS

In this paper the third order nonlinear optical response of a Frenkel chain composed of N dipole-dipole coupled two-level molecules is reviewed. The fundamental electronic excitations of such a system are, in fact, fermions, a property which greatly simplifies the eigenspectrum for multiexciton states. The introduction of site disorder does not disrupt the fermion nature and is therefore easily incorporated into a general expression of the third order nonlinear optical susceptibility.