Structure-Function Relationship in Correlated Oxides

This research line investigates oxides in which the advanced functions are based on strong correlations between electrons. In particular, we study how these functionalities can be increased and controlled. The main investigated oxides belong to the family of perovskites for applications in microelectronics. As an example, we have managed to increase the resistivity by three orders of magnitude by varying the thickness from 20 nm to 100 nm in magnetoresistive films composed of La_0.7Sr_0.3CoO₃ [1] and we have succeeded in controlling a selective growth by MOCVD as a function of the temperature in the case of multiferroic films composed of YMnO₃ (PhD thesis I. Iliescu). The metal/perovskite interfaces, presenting resistive switching properties, are also studied in collaboration with our partners in order to integrate them into ReRAM memories [2-3] (PhD thesis A. Schulman, K. Maas, R. Rodriguez-Lamas). In collaboration with IST in Portugal (PhD thesis T. Nguyen), we have investigated spinel-type oxides and hydroxides and we have shown the development of different innovative electrodes in the form of thin films for redox supercapacitors [4-5].
 

[1] Z. Othmen et al. Applied Surface Science 306, 60 (2014)
Structural, Electrical, and Magnetic Properties of Epitaxial La_0.7Sr_0.3CoO₃ Thin Films Grown on SrTiO₃ and LaAlO₃ Substrates

[2] C. Acha et al. Applied Physics Letters 109, 011603 (2016)
Transport Mechanism Through Metal-Cobaltite Interfaces

[3] S. Bagdzevicius et al. Journal of Materials Chemistry C 7, 7580 (2019)
Superposition of Interface and Volume Type Resistive Switching in Perovskite Nanoionic Devices

[4] T. Nguyen et al. Scientific Reports 7, 39980 (2017)
Layered Ni(OH)₂-Co(OH)₂ Films Prepared by Electrodeposition as Charge Storage Electrodes for Hybrid Supercapacitors

[5] T. Nguyen et al. Energy 126, 208 (2017)
Ni_xCo_1-x(OH)₂ Sheets on Carbon Nanofoam Paper as High Areal Capacity Electrodes for Hybrid Supercapacitors