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Excitonic Instability and Origin of the Mid-Gap States

Michael N. Kiselev
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Abstract

In the framework of the two-band model of a doped semiconductor the self-consistent equations describing the transition into the excitonic insulator state are obtained for the 2D case. It is found that due to the exciton-electron interactions the excitonic phase may arise with doping in a semiconductor stable initially with respect to excitonic transition in the absence of doping. The effects of the strong interactions between electron (hole) Fermi-liquid (FL) and excitonic subsystems can lead to the appearance of the states lying in the middle of the insulating gap.

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Michael N. Kiselev. 1994-05-11. Excitonic Instability and Origin of the Mid-Gap States. https://doi.org/10.1016/0921-4534(94)92384-1

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