As demand for optical communication capacity continues to grow, the 2 µm wavelength region is emerging as a promising new window for future photonic systems. Researchers have developed a high-speed InGaAs/GaAsSb type-II superlattice photodetector that is heterogeneously integrated on silicon via micro-transfer printing. By combining a backside Au reflector with a low-index BCB cavity, the device achieves broadband operation from 0.8 to 2.5 µm and a 57.9% responsivity enhancement at 2 µm, while maintaining 17–18.7 GHz bandwidth and clear 50 Gbps eye diagrams. The work provides a practical route toward broadband, high-speed photodetectors for silicon photonics and next-generation optical interconnects.

Paraxial optical skyrmions, defined by Stokes vectors, have attracted significant attention due to their ability to propagate in free space with preserved topological structures. Recently, this exotic topological structured light has been extended to the spatiotemporal domain, though so far only in the visible and near-infrared regimes. The team led by Academician Zhuang Songlin and Professor Yi Liu at the University of Shanghai for Science and Technology theoretically explores, for the first time, the generation and control mechanisms of extreme-ultraviolet spatiotemporal skyrmions based on the high-harmonic generation process. The discovery is published in the journal PhotoniX.

Researchers from the University of Science and Technology of China proposed and numerically demonstrated a scheme to realize the self-healing effect of non-Hermitian skin modes in photonic Floquet lattices. They introduced the concept of skin mode tunability (SMT), a mechanism in which the spectrum of skin modes localized at one boundary can be tuned via a potential applied at the opposite boundary. Using a tight-binding Floquet Hamiltonian and the beam propagation method (BPM) simulation in coupled helical waveguides with experimentally accessible parameters, the researchers showed that a targeted skin mode can be spectrally isolated and transformed into a self-healing state that recovers its profile after encountering a disturbance. The study provides a general framework for engineering skin modes through local perturbations and for controlling wave dynamics in non-Hermitian photonic systems.

A research team found that tree felling and timber extraction produce different damage patterns in Sal (Shorea robusta)-dominated forests.