A possible role of D^- band in hopping conductivity and metal-insulator transition in 2D structures

V. I. Kozub; N. V. Agrinskaya; S. I. Khondaker; I. Shlimak

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A possible role of D^- band in hopping conductivity and metal-insulator transition in 2D structures

V. I. Kozub·N. V. Agrinskaya·S. I. Khondaker·I. Shlimak

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Abstract

A simple two-band model is suggested explaining recently reported unusual features for hopping magnetoresistance and the metal-insulator transition in 2D structures. The model implies that the conductivity is dominated by the upper Hubbard band (D^- band). Experimental studies of hopping magnetoresistance for Si delta doped GaAs/AlGaAs heterostructure give additional evidences for the model.

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V. I. Kozub, N. V. Agrinskaya, S. I. Khondaker, I. Shlimak. 1999-11-27. A possible role of D^- band in hopping conductivity and metal-insulator transition in 2D structures. https://arxiv.org/abs/cond-mat/9911450

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