Role of the different defects, their population and distribution in the LaAlO3 /SrTiO3 heterostructure's behavior

Hicham Zaid (1) , Marie-Hélène Berger (1) , Denis Jalabert (2) , M. Walls (3) , R. Akrobetu (4) , N.J. Goble (4) , X.P.A. Gao (4) , P. Berger (5) , I. Fongkaew (6) , W. Lambrecht (4) , A. Sehirlioglu (4)

1 CDM - Centre des Matériaux
2 LEMMA - Laboratoire d'Etude des Matériaux par Microscopie Avancée
3 LPS - Laboratoire de Physique des Solides
4 Case Western Reserve University [Cleveland]
5 LEEL - UMR 3685 - Laboratoire d'Etudes des Eléments Légers
6 SUT - Suranaree University of Technology

Hetero-interfaces between epitaxial LaAlO3 films and SrTiO3 substrates can exhibit an insulator-metal transition at a critical film thickness above which a quasi-two-dimensional electron gas forms. This work aims to elucidate the significant role the defects play in determining the sources of non-mobile and mobile carriers, the critical thickness, and the dipolar field screening. A model is built based on a comprehensive investigation of the origin of charge carriers and the advanced analysis of structural factors that affect the electronic properties of these hetero-epitaxial interfaces.

Mots clés: OXIDE INTERFACES; ELECTRON-GAS; CONDUCTIVITY; HETEROINTERFACE; MECHANISM; MOBILITY; STRAIN

Domaines: Matériaux; Science des matériaux [cond-mat.mtrl-sci]

Hicham Zaid, Marie-Hélène Berger, Denis Jalabert, M. Walls, R. Akrobetu, et al.. Role of the different defects, their population and distribution in the LaAlO3 /SrTiO3 heterostructure's behavior. Journal of Applied Physics, 2018, 123 (15), 155304, 5 p. ⟨10.1063/1.5024554⟩. ⟨cea-01775862⟩