Engineering Hall Resistivity Anomalies in Epitaxial SrRuO₃ Thin Films by Mo Doping

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Magnetic transport properties, including the anomalous Hall effect (AHE) and topological Hall effect (THE), are key to understanding charge and spin dynamics.
• These effects are vital for developing advanced spintronic devices.
• Strontium ruthenate (SrRuO3) is a promising material for Hall effect studies due to its ferromagnetism, with potential for manipulation via its spin-orbit-coupled band structure.

Purpose of the Study:

• To investigate the impact of Molybdenum (Mo) doping on the Hall resistivity (ρxy) of epitaxial SrRuO3 thin films.
• To explore the emergence and tunability of a hump anomaly in the Hall resistivity.
• To elucidate the underlying mechanisms responsible for the observed phenomena.

Main Methods:

• Fabrication of epitaxial SrRuO3 thin films with varying Mo doping concentrations.
• Measurement of magnetic transport properties, specifically Hall resistivity (ρxy).
• Analysis using a multi-domain anomalous Hall effect (AHE) model incorporating spatial inhomogeneities and k-space Berry curvature.

Main Results:

• Mo doping was found to enhance the Hall resistivity (ρxy) in SrRuO3 films.
• A tunable hump anomaly in the Hall resistivity was observed and engineered.
• The hump anomaly was successfully attributed to the multi-domain AHE model, linked to inhomogeneities and Berry curvature.

Conclusions:

• The study clarifies the mechanism behind the hump anomaly formation in SrRuO3 films.
• Mo doping offers a viable strategy to enhance the anomalous Hall effect in SrRuO3.
• These findings provide a pathway for improved controllability of spintronic devices utilizing SrRuO3.