Metallic Phase and Metal-insulator Transition in 2d Electronic Systems

TL;DR

This paper discusses the possibility of a metallic phase in two-dimensional electronic systems and proposes experiments to test for its existence, challenging traditional views on localization and insulating behavior.

Contribution

It introduces the idea that a metallic phase can exist in 2D systems and suggests experimental diagnostics to verify this, revising previous theoretical assumptions.

Findings

Existence of a metallic phase in 2D systems supported by experimental observations

Proposed magnetoconductance and tunnelling experiments as diagnostic tools

Predicted a maximum metallic resistivity in the flow diagram

Abstract

The recent experimental observation of a metal-insulator transition in two dimensions prompts a re-examination of the theory of disordered interacting systems. We argue that the existing theory permits the existence of a metallic phase and propose a number of experiments such as magnetoconductance and tunnelling in the presence of a parallel field, which should provide diagnostic tests as to whether a given experimental system is in fact in this regime. We also comment on a generic flow diagram which predicts a maximum metallic resistivity.