Defect-Induced Exchange Bias in a Single SrRuO₃ Layer.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spintronics

Background:

• Exchange bias typically arises from interactions in magnetic multilayers.
• Controlling spintronic properties in single-phase materials is challenging.

Purpose of the Study:

• To investigate the induction of exchange bias in a single strontium ruthenium oxide (SrRuO3) layer using helium ion irradiation.
• To explore the relationship between defect density, magnetic properties, and the emergence of exchange bias.

Main Methods:

• Helium ion irradiation of single SrRuO3 layers with varying fluences.
• Characterization of magnetic properties, including magnetization and Curie temperature.
• Investigation of structural and electronic phase transitions using transport measurements.

Main Results:

• A significant exchange bias field, up to approximately 0.36 T, was achieved in the irradiated SrRuO3.
• Increased irradiation fluence led to suppressed magnetization and Curie temperature.
• Helium ion irradiation induced a metal-insulator transition at low temperatures.
• The observed exchange bias is attributed to the coexistence of magnetic and structural phases induced by defects.

Conclusions:

• Helium ion irradiation is an effective method for inducing and enhancing large exchange bias in single SrRuO3 layers.
• Defect engineering via ion irradiation provides a pathway to tailor spintronic properties in complex oxides.
• The interplay between defects, magnetic phases, and structural transitions is crucial for generating exchange bias.