Room-temperature single-photon emission from β-Ga2O3

Single photon emitters (SPEs) hosted by the wide bandgap semiconductors have the great potential to enable quantum applications at room temperature. Recently, many defect-based SPEs have been discovered in various wide bandgap materials, such as diamond, AlN, SiC, h-BN, GaN and ZnO. Beta-phase gallium oxide (β-Ga₂O₃) is an emerging ultrawide bandgap semiconductor with promising electronic and optoelectronic properties, however, there has been no report on single-photon emission from β-Ga₂O₃ to date. Herein, we present the demonstration of room-temperature photostable single-photon emission from β-Ga₂O₃. We find that the SPEs can be found in a variety of β-Ga₂O₃ including homoepitaxial and heteroepitaxial β-Ga₂O₃ films and commercially available β-Ga₂O₃ wafers. The observed emitters have excellent photophysical characteristics including high purity, high brightness, and linear polarization. First-principles calculations predict that a localized neutral divacancy defect, generated by plasma treatment and activated by annealing, is responsible for the SPEs in β-Ga₂O₃. The high-performance room-temperature SPEs embedded in a technologically mature semiconductor are promising for on-chip scalable integrated devices and quantum technologies.