On the Nature of Localization in Ti doped Si

TL;DR

This paper investigates electron localization in Ti doped Si, revealing that Anderson localization significantly influences the metal-insulator transition, which is crucial for the development of efficient intermediate band solar cells.

Contribution

It applies a novel first principles method to analyze the role of Anderson versus Mott localization in Ti doped Si, advancing understanding of localization mechanisms in intermediate band semiconductors.

Findings

Anderson localization dominates the metal-insulator transition in Ti doped Si.

Mott localization is less significant in this transition.

Implications for designing more efficient intermediate band solar cells.

Abstract

Intermediate band semiconductors hold the promise to significantly improve the efficiency of solar cells, but only if the intermediate impurity band is metallic. We apply a recently developed first principles method to investigate the origin of electron localization in Ti doped Si, a promising candidate for intermediate band solar cells. Although Anderson localization is often overlooked in the context of intermediate band solar cells, our results show that in Ti doped Si it plays a more important role in the metal insulator transition than Mott localization. Implications for the theory of intermediate band solar cells are discussed.