Large Perpendicular Magnetic Anisotropy Induced by an Intersite Charge Transfer in Strained EuVO₂H Films

Area of Science:

• Materials Science
• Solid-State Chemistry
• Condensed Matter Physics

Background:

• Perovskite oxides (ABO3) are crucial in materials science, with intersite charge transfer (ICT) inducing unique phenomena like negative thermal expansion.
• Current methods for achieving ICT rely on cationic substitution or ordering, limiting the scope for novel functionalities.

Purpose of the Study:

• To demonstrate an anionic approach for inducing ICT in perovskite materials.
• To investigate the effects of ICT on the magnetic and conductive properties of EuVO2H.

Main Methods:

• Synthesis and characterization of the oxyhydride perovskite EuVO2H.
• Application of external pressure to bulk EuVO2H and compressive strain to thin films.
• Measurement of magnetic transition temperature (TC) and magnetic anisotropy.

Main Results:

• Bulk EuVO2H exhibits ferromagnetic insulating behavior with a TC of 10 K.
• Pressure/strain induces ICT from EuH to VO2 layers, making the VO2 layer conductive.
• ICT increases TC (up to 4x) and induces significant perpendicular magnetic anisotropy in thin films (<100 nm).

Conclusions:

• An anionic strategy using EuVO2H successfully induces ICT, offering an alternative to cationic approaches.
• The observed changes in magnetic and conductive properties open new avenues for designing functional materials.
• Alternating transition metal/rare earth layers with heteroanions provides a versatile platform for novel material functions.