Beijing Institute of Optoelectronic Technology

Indium phosphide quantum dots (InP QDs) are premier candidates for environmentally friendly displays, yet their industrial utility is limited by complex, multistep synthesis methods requiring intermediate purification. Here, we present a kinetic control and ligand synergy strategy enabling the centrifugation-free, one-pot synthesis of high-performance green InP/GaP/ZnS QDs. By pinpointing the nucleation temperature (250 °C) and optimizing the In:myristic acid ratio (1:4), we establish a dynamic ligand environment that successfully suppresses oxidized indium species (InPOx) formation and nonradiative recombination, as validated by X-ray photoelectron spectroscopy. The resulting green-emitting InP/GaP/ZnS QDs achieved an outstanding photoluminescence quantum yield (PLQY) of 86% and a narrow full width at half-maximum of 44 nm, representing the highest reported PLQY for one-pot synthesized InP QDs with GaP intermediate shells. Quantum dot light-emitting diodes fabricated with these QDs demonstrate stable electroluminescence at 535 nm, achieving a maximum external quantum efficiency of 3.02% and a current efficiency of 12.14 cd A–1. This scalable, centrifugation-free approach effectively bridges the performance gap between one-pot and multistep synthesis, offering a viable pathway toward the industrial manufacturing of environmentally benign QDs for display and lighting applications.

Traditional dehazing methods are difficult to remove dense fog from images, while using deep learning networks for dehazing faces the problem of incomplete dehazing and dim images. This paper designs and implements an image dehazing system based on deep learning and image enhancement. The proposed method is based on the FFA (Feature Fusion Attention) algorithm model, we adds Dark Channel Enhancement (DCE) module and Automatic Color Equalization (ACE) module to achieve image enhancement in dense fog scenes. The DCE module enhances overall dehazing by estimating transmittance and atmospheric light, while the ACE module can achieve image enhancement based on multi-scale detail enhancement and contrast stretching. The proposed algorithm can significantly improve target color contrast, enhance brightness clarity. Through experimental testing, the improved model significantly improves the image clarity in actual scenes under thick fog while maintaining fast processing capabilities. The average peak signal-to-noise ratio and structural similarity reach 22.65dB and 88.43%, respectively, and the performance is better than traditional dehazing models.

This work presents a high-efficiency, single-drive U-shape MOS capacitor Michelson interferometer modulator. The introduced U-shape structure enables vertical compression of the optical mode, which significantly enhances the modulation efficiency without compromising series resistance or loaded capacitance. Furthermore, by adopting a Michelson interferometer configuration, the device doubles the effective modulation length through bidirectional light propagation, while maintaining an unchanged capacitance. The designed device achieves a high modulation efficiency of 1.08 V·mm and achieves 50 Gbaud/s operation with an extinction ratio about 2.3 dB under a low 2 Vpp drive voltage. The proposed U-shape MOS capacitor modulator reduces reliance on external driver circuits in OIO and CPO transmitters, offering a promising solution for energy-efficient and compact electro-optic modulators.

Silicon-based optoelectronics, which integrates electronics and photonics, has emerged as a key technology for miniaturizing optical communication and sensing systems. Its key advantages include high CMOS process compatibility, low die cost, a small footprint, and low power consumption, making it a promising solution for realizing efficient and reliable optical networks. Our research has focused on three critical components for on-chip integrated optical communication and sensing networks: high-speed silicon modulators, hybrid wavelength-mode-polarization (de) multiplexers, and high-gain waveguide amplifiers. Notably, the waveguide amplifier, functioning as a post-amplifier, is positioned on the backside of the modulator. Its role is to amplify the power of multi-wavelength and multi-mode signals following (de) multiplexing. This amplification effectively compensates for optical transmission losses, resulting in improved signal quality and extended transmission distances, thereby advancing the performance of optical communication and sensing systems.

Electroencephalography (EEG)-based brain computer interface (BCI) systems hold significant promise across diverse applications; however, their performance is compromised by pervasive physiological artifacts that degrade signal fidelity. While current deep neural networks (DNNs) improve artifact rejection, their high computational cost precludes deployment in wearable BCIs systems. Here, we introduce STAND-Net (Spiking Temporal Attention autoeNcoDer Network), a neuromorphic architecture that leverages event-driven spiking neurons to achieve ultra-efficient, high-fidelity EEG artifact removal. STAND-Net combines a spike-convolution encoder-decoder with leaky integrate-and-fire neurons to model spatiotemporal EEG dynamics, a dilation-enhanced residual backbone capturing long-range dependencies, and a spike-rate attention mechanism dynamically localizing artifacts via neuronal firing patterns. The system demonstrates >3.7 dB improvement in signal-to-distortion ratio over state-of-the-art methods across diverse artifacts while consuming 97.98% less power than comparable DNNs. Crucially, downstream BCI classification accuracy increased by 6.64% using STAND-Net-processed signals. This work establishes a neuromorphic framework for low-power and high quality EEG artifact removal in wearable BCI systems.

Abstract Tapered lasers are extensively employed in high power single-mode lasing, yet still suffering from the potential formation of higher-order transverse modes in the tapered region, which severely degrades the laser beam quality. Herein, we propose a novel supersymmetric segmented tapered laser to achieve stable fundamental transverse mode operation. Our design features a three-segmented tapered waveguide along the light propagation direction, with sub-waveguides of varying widths flanking each main waveguide segment. The main waveguides measure 8 μm, 12 μm, and 16 μm in width. Specifically, the 8 μm main waveguide has a corresponding subsidiary waveguide of 2.67 μm; the 12 μm main waveguide has two subsidiary waveguides measuring 4.82 μm and 6.63 μm; and the 16 μm main waveguide has two subsidiary waveguides measuring 7.13 μm and 3.68 μm. Based on coupled-mode theory, we systematically analyzed the coupling coefficients under different inter-waveguide spacings, leading to an optimized spacing of 1.2 μm through comprehensive theoretical simulations and fabrication compatibility constraints. Furthermore, phase-shifted gratings were integrated between tapered waveguide segments to enable precise longitudinal mode selection. This synergistic design could successfully realize robust single-mode operation, offering a scalable framework for on-chip integrated high-power, high-beam-quality tapered lasers.

The course of physical optics is committed to promoting a learning-centered teaching model through the transformation of teaching subjects. This paper designs and implements a basic linear polarization optical scene renderer based on path tracing and ray tracing algorithms, which carries out high-precision simulation of the propagation and interaction of polarized light in the scene and generates dynamic visual effects of the polarized light field. The study verifies the simulation accuracy of the renderer for the Fresnel reflection of polarized light at different angles of incidence by means of "virtual-real combination" of experiments and rendering, effectively improving students' understanding and application ability of polarization optics theory. This research provides new tools with quantitative verification functions and visual support for the teaching experiments of Physical Optics and Optical Principles courses, which is helpful to promote the digital transformation of optical teaching.