β Scribed by C. Mavroyannis
No coin nor oath required. For personal study only.
An effective Hamiltonian is established which describes the excitation spectrum of independent quasiparticles arising from the coherent electron-exciton pairing in molecular solids of the charge-transfer type. This Hamiltonian is then used to study the interaction Of the quasiparticles with an external transverse electromagnetic field. An expression for the dielectric function is derived which describes the dielectric properties of the system. In the presence of electron-exciton pairing and in the long-wavelength limit, the diamagnetic current is finite and is of the London type, indicating the existence of the Wleissner effect. The corrections to the London value for the diamagnetic current depend on the magnitudes of the binding energy of the exciton, the gap function, and the energy difference between the excited and ground states of the system. In the absence of electron-exciton pairing, the diamagnetic current vanishes and the dielectric function corresponds to that for the exciton band.
π SIMILAR VOLUMES
The interaction between an excited electron and a large-radius exciton ( Wannier-Mott exciton) has been studied in the visible and ultra-violet frequency regions for a two-level system of a molecular solid. Using a self-consistent approach, it is shown that at low temperatures and when certain condi
A simple model of the coupling between the Frenkel exciton and charge transfer states is proposed and discussed.