Superconductivity-type fluctuations in the electronic spectra of charge-transfer organic solids

✍ Scribed by C. Mavroyannis

• Publisher: Springer US
• Year: 1975
• Tongue: English
• Weight: 622 KB
• Volume: 20
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00117798

✦ Synopsis

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 conditions prevail, a bound-state may exist arising from the electron-exciton pairing. The excitation spectrum is found to be of the superconductivity type and the electronexciton quasiparticle migrates through the crystal with definite energy and wave vector. The gap function due to the electron-exciton pairing is calculated at zero temperature and then the expression for the transition temperature is established. A formula for the ground-state energy is derived corresponding to the electron-exciton pairing and a discussion of the parameters that appear in the theory is presented.

*The distribution function (~,t,v~[_~9,o~k+bq,~) describes the coherent state of three Fermi particles with total momentum equal to zero and it will be calculated self-consistently.