Superparamagnetic state in La0.7Sr0.3MnO3 thin films obtained by rf-sputtering
M C Ramírez Camacho1,2, C F Sánchez Valdés3, M Curiel2
1Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, AP 14, 22860, Ensenada, Baja California, México.
Scientific Reports
|February 15, 2020
Summary
A novel superparamagnetic state was observed in lanthanum strontium manganese oxide (LSMO) thin films grown on silicon substrates. These findings suggest potential applications in next-generation spintronic nanodevices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Lanthanum strontium manganese oxide (LSMO) is a promising material for spintronic applications.
- Controlling the magnetic properties of thin films is crucial for device development.
- Silicon-based substrates offer a platform for integrating novel electronic materials.
Purpose of the Study:
- To investigate the magnetic properties of LSMO thin films grown on SiOx/Si(100) substrates.
- To explore the influence of film thickness on magnetic behavior.
- To assess the potential of these films for spintronic nanodevices.
Main Methods:
- Radio frequency (rf) sputtering for thin film deposition.
- X-ray diffraction for structural analysis.
- Magnetization measurements (ZFC-FC curves, M(H) hysteresis loops) to characterize magnetic states.
Main Results:
- Observation of a novel superparamagnetic state in nanostructured LSMO films.
- Thickness-dependent transition from superparamagnetic to ferromagnetic states.
- Thinner films (40-60 nm) exhibit superparamagnetism due to interacting nanoregions.
- Thicker films (140 nm) show typical ferromagnetic order.
- Higher coercive fields compared to previously reported LSMO.
Conclusions:
- LSMO films grown on SiOx/Si exhibit unique magnetic properties, including a thickness-dependent superparamagnetic state.
- The nanostructure and surface spin-glass boundaries play a critical role in the observed magnetic behavior.
- These findings highlight the potential of LSMO thin films for integration into silicon-based spintronic nanodevices.
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