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Ferromagnetic 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. Semiconductors: Maintaining magnetism at high temperature A magnetic semiconductor that retains its magnetic properties at high temperatures has been developed by researchers in China and Germany. Semiconductor materials do much of the processing in computers and cell phones whereas magnetic materials store and retrieve information. A magnetic semiconductor merges these two functions in a single material and offers unique functionality not seen in the other materials. However, the magnetic properties of most of the known magnetic semiconductors disappear at high temperatures, limiting their application. Youwen Long from the Beijing National Laboratory for Condensed Matter Physics and colleagues used high pressures and high temperatures to create a SrCrFeO compound. This perovskite (a compound with a similar crystal structure to CaTiO3) demonstrated ferromagnetic behavior up to 600 K. Ferromagnetic semiconductors are promising candidates for high-performance multifunctional spintronic devices due to the peculiar magneto-electric and magneto-optical properties. However, the low spin ordering temperature limits their applications. By using high pressure to stabilize the crystal structure and oxygen content, an oxygen-deficient perovskite SrCr0.5Fe0.5O2.875 was synthesized. This compound displays ferromagnetic behavior with a spin ordering temperature as high as 600 K. Benefiting from the semiconducting direct bandgap (~2.28 eV), a field-tunable green fluorescent effect is observed. This work opens up a new avenue for research on room-temperature multifunctional materials with coupled magnetic, electrical, and optical performance. [ABSTRACT FROM AUTHOR]