Review of Continuum excitons

   1991-1992.We formulated a concept of a new type of elementary excitations in semiconductors, i.e. excitons in which an electron is bound with a continuum of holes, rather than with a single hole. The possibility of the formation of biexciton states was considered and a hypothesis of a biexciton mechanism of arising of a high-temperature superconductivity was put forward. The results obtained are presented in ( /1/ ).

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   1992-1993.We introduced a concept of a new type of elementary excitations in solid states, i.e. continuum excitons ( /2/ ). In semiconductors these correspond to a an electron bound state with a continuum of holes rather than with a single hole (as in the case of Frenkel exciton or Wannie-Mott exciton). Continuum excitons can be of importance in calculation of electron states in superatoms and in quantum dots.

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   1993-1998.A quantum theory of the interaction between an electron and plasmons was developed ( /5/, /6/, /7/ ). In particular, it was shown that plasmon exchange can lead to a bound state of two electrons in the case of both weak and strong coupling. The results obtained may be useful in explaining the nature of high-temperature superconductivity.