Ambiguity Free Characterization of Metal-Insulator Transition in Disordered Fermionic Systems

Abstract

Unambiguous characterization of metal insulator transi-tion in disordered system is an important problem. One of the most widely used indicator to do this charac-terization is inverse participation ratio (IPR). IPR can capture the signature of metal insulator transition but it is not free of ambiguity. However, a much more effec-tive and unambiguous approach to identify an insulating or metallic state is to use a localization tensor which is based on the idea of Kohn’s localization. We have stud-ied the one-dimensional Aubry-Andr`e model with cosine modulated disorders. We have used both rational and irrational modulation of the disorder potential to show that it is easier to conclude about the electronic state if localization tensor is used for characterization.