➀ Researchers at EPFL and IBM Research Europe have developed a novel optical amplifier using gallium phosphide-on-silicon dioxide technology, which achieves unprecedented broadband signal amplification in a compact photonic chip.

➁ The traveling-wave parametric amplifier (TWPA) demonstrates over 10 dB of gain across a 140 nm bandwidth, surpassing traditional erbium-doped fiber amplifiers (EDFAs).

➂ This breakthrough in optical amplification holds potential applications in data centers, AI processors, high-performance computing, and even autonomous vehicle LiDAR systems.

The Fraunhofer Heinrich-Hertz-Institut (HHI) is working on the further development of passive optical networks (PON) in the PONTROSA project to promote fiber optic expansion and explore new applications for the technology. The institute, together with project partners, will develop new electronic and optical subsystems to significantly increase the transmission capacity of future PONs. The project, funded by the Federal Ministry of Education and Research with 3.8 million euros, will run for three years until September 2027.

Passive optical networks (PON) have become prevalent over active optical networks (AON) for their cost-effectiveness and simplicity. However, to meet future demands and new application areas, such as connecting data centers and distributed mobile stations, the achievable data rates need to be significantly expanded.

The project team will design, fabricate, and integrate optimized electronic and photonic integrated circuits into a complete system. The researchers will also analyze the requirements for digital signal processing and develop appropriate methods.

➀ 21年前，当移动互联网刚刚兴起时，电信行业与现在大不相同；

➁ 根据剑桥顾问公司（CCL），3G是为了降低成本，而不是用于多媒体数据传输，如流媒体视频和视频电话；

➂ 语音仍然是杀手级应用，运营商的问题在于过去两年ARPU（每用户平均收入）下降了20%；

➃ CCL对无线局域网（802.11）持怀疑态度，认为其能耗高，不适合用户密集的地方。

➀ The Fraunhofer Heinrich-Hertz-Institut (HHI) has initiated the QR.N project to develop interconnected quantum repeaters for secure end-to-end communication networks.

➁ The project is funded by the German Federal Ministry of Education and Research and is set to run from January 2025 to December 2027.

➂ Quantum networks ensure secure data transmission through the principles of quantum mechanics, particularly quantum entanglement, making any tampering or query of quantum states immediately detectable.

Conventional lenses, which bend light through glass or plastic, are often bulky, heavy, and offer limited control over light waves. In contrast, metaoptics, consisting of flat surfaces with tiny structures called metaatoms, allow for precise control of light, including its phase, amplitude, and polarization. This precision enables the replacement of multiple optical components with a single metaoptical surface, reducing the size of optical systems without compromising their performance.

At the Hannover Messe, researchers from the Karlsruhe Institute of Technology (KIT) demonstrated an optical component that enables highly efficient light control at steep incident angles, overcoming previous limitations. The researchers developed a metagrating with four times the efficiency of conventional systems, allowing unprecedented control over light under challenging conditions.

Metaoptics are particularly suitable for cameras, sensors, and augmented-reality displays due to their ability to enhance functionality while reducing the size of optical systems. Potential applications include material sorting, quality control, medical imaging, microscopy, and solar cells. They could also significantly benefit robotics and autonomous driving, which rely on object recognition.