Dipole trap model for the metallic state in gated silicon-inversion layers

TL;DR

This paper refines the dipole trap model to better explain the metallic state in high-mobility silicon MOS structures, incorporating spatial and energy distributions of trap states, aligning well with experimental data.

Contribution

The authors develop a more precise numerical version of the dipole trap model, including spatial depth and energy distribution of traps, to explain metallic behavior in Si-MOS layers.

Findings

Trap states at specific energies induce metallic behavior.

Model predictions align with experimental observations.

Refined model improves understanding of metallic state mechanisms.

Abstract

In order to investigate the metallic state in high-mobility Si-MOS structures, we have further developed and precised the dipole trap model which was originally proposed by B.L. Altshuler and D.L. Maslov [Phys. Rev. Lett.\ 82, 145 (1999)]. Our additional numerical treatment enables us to drop several approximations and to introduce a limited spatial depth of the trap states inside the oxide as well as to include a distribution of trap energies. It turns out that a pronounced metallic state can be caused by such trap states at appropriate energies whose behavior is in good agreement with experimental observations.