Dynamic Control of Crystallographic Orientation and Multiferroicity in Epitaxial YCrO ₃ Films via Oxygen Pressure Modulation

Crystallographic orientation plays a crucial role in determining the functional properties of thin films. Traditional methods for controlling orientation typically rely on selecting different substrates or incorporating complex buffer layers of varying thickness, which limits flexibility and scalability. Here, we introduce an approach to modulate the crystallographic orientation of multiferroic YCrO₃ thin films by adjusting oxygen pressure during pulsed laser deposition, enabling in situ growth of distinct orientations on a single (100) oriented SrTiO₃ substrate. This method eliminates the need for multiple substrates while preserving oxygen stoichiometry through postgrowth annealing, ensuring structural stability. The resulting orientation strongly influences ferroelectric polarization and magnetic anisotropy, highlighting the intrinsic coupling between crystal structure and functionality. Structural analysis reveals that oxygen pressure modulates lattice constants and promotes preferential orientations, underscoring its potential as a versatile tool for engineering both crystallographic and functional properties in complex oxide thin films.