High-Temperature Ferroic Glassy States in SrTiO_{3}-Based Thin Films

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid State Chemistry

Background:

• Disordered ferroics offer low-energy magnetoelectric applications but suffer from low transition temperatures and weak polarization/magnetization.
• Existing challenges limit the practical use of ferroic materials in advanced devices.

Purpose of the Study:

• To engineer disordered ferroic materials with enhanced properties for next-generation magnetoelectric devices.
• To investigate the mechanism behind coexisting spin and dipole reentrant glass states in SrTiO3 films.

Main Methods:

• Homoepitaxial growth of SrTiO3 films.
• Manipulation of local symmetry through control of Ti/O defects.
• Atomic-scale investigation of structural and electronic properties.

Main Results:

• Achieved coexisting spin and dipole reentrant glass states in SrTiO3 films.
• Realized room-temperature saturation magnetization (~10 emu/cm³) and spontaneous polarization (~25 μC/cm²).
• Observed high transition temperatures (e.g., 1100 K Curie temperature for polarization).

Conclusions:

• Local symmetry breaking in Ti/O-defective SrTiO3 drives unusual slush states and enhances ferroic properties.
• The findings advance the understanding of ferroic glass couplings and offer a pathway for controlling magnetic and polar orderings simultaneously.
• The developed approach is applicable to other perovskite oxides for novel device functionalities.