Collective oscillations of free electrons generate plasmons on the surface of a material. A whispering-gallery microcavity effectively confines the light field on its surface based on the total reflection from its internal wall. When these two kinds of electromagnetic waves meet each other, the stimulated emissions from an individual ZnO microrod were enhanced more than 50-fold and the threshold was reduced after the whispering-gallery microcavity was coated with a monolayer of graphene and Al nanoparticles. The improvement of the lasing performance was attributed to the synergistic energy coupling of the graphene/Al surface plasmons with ZnO excitons. The lasing characteristics and the coupling mechanism were investigated systematically. Open image in new window
Micro-LED arrays exhibit high brightness, a long lifespan, low power consumption, and a fast response speed. In this paper, we have proposed a series-biased micro-LED array by using a nitride layer with multi-quantum wells epitaxial on sapphire substrate. The III-nitride multiple quantum wells serving as the micro-LED active material enable both luminescence and detection functionalities. The micro-LED array combines lighting, detection, and communication capabilities. We have conducted a thorough analysis of the micro-LED array’s optoelectronic features in both lighting and detection modes. We also explore visible light communication performance across different arrangements of single micro-LED devices within the series-biased array. Our research achieves 720p video transmission via visible light communication using the micro-LED array, supporting a communication rate of up to 10 Mbps. Our contributions encompass the successful integration of lighting and detection functions and a comprehensive assessment of optoelectronic and communication performance. This study highlights the multifunctional micro-LED array’s potential as a transceiver terminal in visible light communication systems, expanding its applications from smart lighting to visible light communication and photonic integrated chips. These innovations enhance our understanding of micro-LED technology and its versatile applications.
Gallium oxide (Ga2O3), an ultrawide bandgap semiconductor, is an ideal material for solar-blind photodetectors, but challenges such as low responsivity and response speed persist. In this paper, one-dimensional (1D) Ga2O3 nanorods were designed to achieve high photodetection performance due to their effective light absorption and light field confinement. Through modulating source concentration, pH value, temperature, and reaction time, 1D β-Ga2O3 nanorods were controllably fabricated using a cost-effective hydrothermal method, followed by post-annealing. The nanorods had a diameter of ~500 nm, length from 0.5 to 3 μm, and structure from nanorods to spindles, indicating that different β-Ga2O3 nanorods can be utilized controllably through tuning reaction parameters. The 1D β-Ga2O3 nanorods with a high length-to-diameter ratio were chosen to construct metal-semiconductor-metal type photodetectors. These devices exhibited a high responsivity of 8.0 × 10−4 A/W and detectivity of 4.58 × 109 Jones under 254 nm light irradiation. The findings highlighted the potential of 1D Ga2O3 nanostructures for high-performance solar-blind ultraviolet photodetectors, paving the way for future integrable deep ultraviolet optoelectronic devices.