| Autor: |
Agudelo-Estrada Santiago, Barrett Nick, Lubin Christophe, Wolfman Jérôme, Negulescu Beatrice, Andreazza Pascal, Ruyter Antoine |
| Jazyk: |
angličtina |
| Rok vydání: |
2022 |
| Předmět: |
|
| Zdroj: |
EPJ Web of Conferences, Vol 273, p 01008 (2022) |
| Druh dokumentu: |
article |
| ISSN: |
2100-014X |
| DOI: |
10.1051/epjconf/202227301008 |
| Popis: |
The interface of a La0.7Sr0.3MnO3/SrTiO3 bilayer was modulated by introducing 3 unit cells of Ba1-xSrxTiO3 using Combinatorial Pulsed Laser Deposition. A wide range of chemical compositions was studied within the same sample, with BSTx stoichiometry variable from 0.5 to 1 along Y-axis, while the SrTiO3 overlayer thickness was modified along the X direction [Fig. 1(a)]. We performed high-resolution, laboratory-based angle-resolved XPS studies of the BSTx film surface providing information on the thickness and composition of the surface and sub-surface layers. Based on the attenuation of the La 3d corelevel photoemission signal from the La0.7Sr0.3MnO3 bottom layer, the BST layer is 1.2 nm thick. XPS Ba 3d5/2 core-level spectra were acquired at positions corresponding to different nominal Ba/Sr stoichiometry. In all measurements, the Ba 3d5/2 core-level spectra can be represented by two main components, i.e. one component at higher binding energy (BE = 780.54 eV) corresponding to surface contribution and the other one at lower binding energy (BE = 778.92 eV) corresponding to sub-surface contribution (Figs. 2 and 3). Going from normal to 60° emission angle and using a 3-unit cell thick film model, the surface to sub-surface intensity ratio clearly evolves providing evidence of a Ba-rich surfactant. The surfactant effect is more significant for lower nominal Ba stoichiometry. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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