Weak localization in the 2D metallic regime of Si-MOS

TL;DR

This study investigates weak localization effects in high-conductance Si-MOS 2D systems, revealing phase coherence behavior and the absence of strong electron-electron interaction effects within a specific temperature and concentration range.

Contribution

It provides new insights into phase coherence and quantum effects in 2D Si-MOS structures at high conductance levels, with detailed analysis of weak localization and spin-orbit scattering.

Findings

Phase coherence time equals momentum relaxation time at 10 K.

Nearly 100 times longer phase coherence time at lowest temperature.

Only weak logarithmic conductivity corrections observed.

Abstract

The negative magnetoresistance due to weak localization is investigated in the two-dimensional metallic state of Si-MOS structures for high conductance values between 35 and 120 e^2/h. The extracted phase coherence time is equal to the momentum relaxation time at 10 K but nearly 100 times longer at the lowest temperature. Nevertheless, only weak logarithmic corrections to the conductivity are present in the investigated temperature and concentration range thus proving the absence of strong quantum effects due to electron-electron interaction. From saturation effects of the phase coherence time a lower boundary for spin-orbit scattering of about 200 ps is estimated.