High-temperature ferromagnetic semiconductor with a field-tunable green fluorescent effect

Abstract

AbstractFerromagnetic semiconductors with luminescent effects provide a unique platform for studying magneto-electric-optical multifunctional devices. However, little is known about such materials with spin ordering well above room temperature. By using a unique high-pressure annealing method, a Cr and Fe disordered perovskite oxide SrCr0.5Fe0.5O2.875 (SCFO) with a simple cubic structure was prepared. Magnetic measurements demonstrated the ferromagnetic behavior with a spin ordering temperature as high as 600 K. In contrast to metallic SrCrO3 and SrFeO3, SCFO, with a moderate oxygen deficiency, is a direct bandgap semiconductor with an energy gap of 2.28 eV, which is within the visible light region. As a consequence, SCFO displays a green fluorescent effect arising from the d–p bonding and anti-bonding states. Moreover, the photoluminescence intensity can be tuned by a magnetic field. This work opens up a new avenue for research on room-temperature multifunctional materials with coupled magnetic, electrical, and optical performance.