Xin Li

The security of virtual power plant (VPP) communication networks is paramount, particularly owing to growing increase in the reliance on distributed energy resources (DERs) using cloud-edge architectures. VPPs are increasingly vulnerable to cyber intrusion owing to the large number of access devices involved. Existing intrusion detection methods often face challenges in addressing the complexity of VPP networks, and lack adaptability to diverse attack patterns. To address the dynamic nature of VPPs, this study proposes a novel intrusion detection approach called dynamic detection combining transformer with feature filtering (DTF-VPP), which integrates principal component analysis (PCA) with a transformer-based model to improve the detection efficiency and accuracy. The key contributions of this study include a feature selection process that uses PCA to reduce the model complexity, and a dynamic loss-weighting mechanism that adapts to high-frequency attacks. The experimental results on the NSL-KDD dataset demonstrate that DTF-VPP outperforms conventional models in terms of the accuracy and F1-score. Therefore, this approach offers a scalable and adaptive solution for enhancing the security of VPPs against cyber threats.

The development of GaN-based photonic integrated chips has attracted significant attention for visible light communication systems due to their direct bandgap and excellent optical properties across the visible spectrum. However, achieving compact and efficient light routing through bent waveguides remains challenging due to high insertion losses. This paper presents a comprehensive investigation of GaN bent waveguides optimization for visible light photonic integrated chips. Through systematic simulation analysis, we examined the effects of bending angle, process optimization approaches, and geometric parameters on insertion loss characteristics. The back-side thinning process demonstrates superior performance compared to front-side etching, reducing the insertion loss of 90° bends from 1.80 dB to 0.71 dB. Further optimization using silver reflection layers achieves an insertion loss of 0.57 dB. The optimized structure shows excellent performance in the blue-green spectral range (420–500 nm) with insertion losses below 0.9 dB, providing practical solutions for compact GaN photonic integrated chips in visible light communications.

Light source and photodetector are necessary elements for liquid concentration sensing system. Normally, two different devices are needed to realize these functions. The coexistence of emission and detection properties in multi-quantum well light emitting diodes (MQWs LEDs) brings convenience to the design of new concentration sensors. In this letter, we present a transmission-type sensing module using two identical AlGaInP red LEDs. With a designed collimation system, any two LEDs can form a sensing channel. Concentration-induced optical signal changes will be transformed into various photocurrents on the receiving side and realize a sensing. Choosing methylene blue solution as the tracer agent, the sensing performance of the system is evaluated. The sensor can detect methylene blue solution concentrations in the range of 0 to $24.23~\mu $ mol/L, providing a novel measurement approach for monitoring substances in wastewater.

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.

Micro-nano optomechanical accelerometers are widely used in automobile, aerospace, and other industrial applications. Here, we fabricate mechanical sensing components based on an electrically pumped GaN light-emitting diode (LED) with a beam structure. The relationship between the blueshift of the electroluminescence (EL) spectra and the deformation of the GaN beam structure based on the quantum-confined Stark effect (QCSE) of the InGaN quantum well (QW) structure is studied by introducing an extra mass block. Under the equivalent acceleration condition, in addition to the elastic deformation of GaN-LED, a direct relationship exists between the LED’s spectral shift and the acceleration’s magnitude. The extra mass block (gravitational force: 7.55×10⁻¹¹ N) induced blueshift of the EL spectra is obtained and shows driven current dependency. A polymer sphere (PS; gravitational force: 3.427×10⁻¹² N) is placed at the center of the beam GaN-LED, and a blueshift of 0.061 nm is observed in the EL spectrum under the injection current of 0.5 mA. The maximum sensitivity of the acceleration is measured to be 0.02 m/s², and the maximum measurable acceleration is calculated to be 1.8×10⁶ m/s². It indicates the simultaneous realization of high sensitivity and a broad acceleration measurement range. This work is significant for several applications, including light force measurement and inertial navigation systems with high integration ability.

III-nitride LEDs offer a solution for ultraviolet (UV) high-speed communication as a transmitter with high performance. This paper focuses on a transmitter with AlGaN/InGaN multi-quantum wells (MQWs) for UV communication. The transmitter is realized on a GaN-on-silicon platform by a double etching process. The emission region of the transmitter with a small area is beneficial for improving the data rate of UV communication. The emission peak keeps stable at 376.48 nm in the UVA band. The transmission with 300 Mbps is obtained in a UV communication system setup with on-off keying (OOK) modulation. We realize a digital signal transmission up to 760 Mbps by bit-loading discrete multi-audio (DMT) modulation.