Conducting interfaces between amorphous oxide layers and SrTiO_3(110) and SrTiO_3(111)

Interfaces between (110) and (111)SrTiO_3 (STO) single crystalline substrates and amorphous oxide layers, LaAlO_3 (a-LAO), Y:ZrO_2 (a-YSZ), and SrTiO_3 (a-STO) become conducting above a critical thickness tc. Here we show that t_c for a-LAO is not depending on the substrate orientation, i.e. t_c (a-...

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Detalles Bibliográficos
Autores: Scigaj, Mateusz, Gázquez, Jaume, Varela Del Arco, María, Fontcuberta Griñó, Josep, Herranz Casabona, Gervasi, Sánchez Barrera, Florencio
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/24360
Acceso en línea:https://hdl.handle.net/20.500.14352/24360
Access Level:acceso abierto
Palabra clave:537
Oxide interfaces
Oxygen vacancies
LaAlO_3/SrTiO_3
Física (Física)
22 Física
Descripción
Sumario:Interfaces between (110) and (111)SrTiO_3 (STO) single crystalline substrates and amorphous oxide layers, LaAlO_3 (a-LAO), Y:ZrO_2 (a-YSZ), and SrTiO_3 (a-STO) become conducting above a critical thickness tc. Here we show that t_c for a-LAO is not depending on the substrate orientation, i.e. t_c (a-LAO/(110)STO) ≈ t_c(a-LAO/(111)STO) interfaces, whereas it strongly depends on the composition of the amorphous oxide: t_c(a-LAO/(110)STO) < t_c(a-YSZ/(110)STO) < t_c(a-STO/(110)STO). It is concluded that the formation of oxygen vacancies in amorphous-type interfaces is mainly determined by the oxygen affinity of the deposited metal ions, rather than orientational-dependent enthalpy vacancy formation and diffusion. Scanning transmission microscopy characterization of amorphous and crystalline LAO/STO(110) interfaces shows much higher amount of oxygen vacancies in the former, providing experimental evidence of the distinct mechanism of conduction in these interfaces.