Size-dependent electronic eigenstates of multilayer organic quantum wells

A detailed theoretical treatment is given of eigenfunctions and eigenenergies of a multilayer organic quantum well sandwiched between two different dielectric media. The abrupt change of dielectric constants at the interfaces distorts the wave function and results in there being possible surface states in addition to propagating states. The proper boundary conditions are accounted for by the method of image charges. Analytic criteria for the existence of surface states are established using the nearest-layer approximation; they depend not only on the intralayer and interlayer parameters but also on the number of layers. The size dependence together with the dependence on signs and relative magnitudes of the structure parameters fully determine the energy spectrum of propagating states as well as the number and the location of surface states.