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arXiv · 1910.06303

Two-dimensional system of strongly interacting electrons in silicon (100) structures

V. T. Dolgopolov
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Abstract

Studies of different experimental groups that explore the properties of a two-dimensional electron gas in silicon semiconductor systems ((100) Si metal-oxide-semiconductor field-effect transistors (MOSFETs) and (100) SiGe/Si/SiGe quantum wells) in the vicinity of the metal-insulator transition are described and critically analyzed. Results are identified that are common to all research: (i) the effective mass of electrons measured at the Fermi level in the metallic regime increases as the electron density decreases and, if extrapolated, tends to diverge; (ii) the behavior of the energy-averaged mass in the metallic region is quite different in the two systems: in Si-MOSFETs, it also exhibits a tendency to diverge, while in the SiGe/Si/SiGe quantum wells it saturates in the limit of low electron densities; (iii) there is a small number (depending on the sample quality) of localized electrons in the metallic phase; (iv) the properties that the electron system exhibits in the insulating phase in the vicinity of the metal-insulator transition are typical of amorphous media with a strong coupling between particles.

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V. T. Dolgopolov. 2019-10-14. Two-dimensional system of strongly interacting electrons in silicon (100) structures. https://doi.org/10.3367/ufne.2018.10.038449

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