Irreversible Multi‐Band Effects and Lifshitz Transitions at the LaAlO3/SrTiO3 Interface Under Field Effect. (25th January 2021)

• Record Type: Journal Article
• Authors: Pallecchi, Ilaria; Lorenzini, Nicolò; Safeen, Mian Akif; Can, Musa Mutlu; Di Gennaro, Emiliano; Granozio, Fabio Miletto; Marré, Daniele
• Is Part Of: Advanced Electronic Materials. Volume 7:Number 3(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-25
• Subjects: field effect -- multiband transport -- oxide interfaces; Materials -- Electric properties -- Periodicals; Materials science -- Periodicals; Magnetic materials -- Periodicals; Electronic apparatus and appliances -- Periodicals; 537
• DOI: 10.1002/aelm.202001120
• Languages: English
• ISSNs: 2199-160X

Abstract

Abstract: In this work, the irreversible effects of an applied electric field on the magnetotransport properties of LaAlO3 /SrTiO3 conducting interfaces are investigated, with focus on their multiband character. Samples of different types, namely with either crystalline or amorphous LaAlO3 overlayer, are studied. The two‐band analysis highlights the similarity of the electronic properties of crystalline and amorphous interfaces, regardless much different carrier densities and mobilities. Furthermore, filling and depletion of the two bands follow very similar patterns, at least in qualitative terms, in the two types of samples. In agreement with previous works on crystalline interfaces, it is observed that an irreversible charge depletion takes place after application of a first positive back gate voltage step. Such charge depletion affects much more, in relative terms, the higher and three‐dimensional d yz, d zx bands than the lower and bidimensional d xy, driving the system through the Lifshitz transition from two‐band to single band behavior. The quantitative analysis of experimental data evidences the roles of disorder, apparent in the depletion regime, and temperature. Noteworthy, filling and depletion of the two bands follow very similar patterns in crystalline and amorphous samples, at least in qualitative terms, regardless much different carrier densities and mobilities. Abstract : Reversible and irreversible effects of an electric field on the magnetotransport properties of LaAlO3 /SrTiO3 interfaces are explored within a multiband framework. Irreversible charge depletion takes place after first application of a positive back gate voltage and it involves much more, in relative terms, the higher three‐dimensional d yz, d zx bands than the lower bidimensional d xy, driving the system through a Lifshitz transition.