The National Institute of Information and Communications Technology (NICT) has successfully demonstrated 2 Tbit/s Free-Space Optical (FSO) communication using small optical communication terminals that can be mounted on satellites and HAPS, marking a world first for this technology.

This experiment involved horizontal free-space optical communication between two types of small portable optical terminals developed by NICT: a high-performance FX (Full Transceiver) installed at NICT Headquarters (Koganei, Tokyo) and a simplified ST (Simple Transponder) installed at an experimental site 7.4 km away (Chofu, Tokyo). Despite the difficult conditions of an urban environment with atmospheric turbulence that disrupts laser beams, the system maintained a stable total communication speed of 2 Tbit/s via Wavelength Division Multiplexing (WDM) transmission of 5 channels (400 Gbit/s each). This is the first time in the world that terabit-class communication has been realized using terminals miniaturized enough to be mounted on satellites or HAPS.

Moving forward, NICT plans to further miniaturize the terminals for implementation onboard a 6U CubeSat. NICT aims to conduct free-space optical communication demonstrations at speeds of up to 10 Gbit/s between a Low Earth Orbit (LEO) satellite (altitude approx. 600 km) and the ground in 2026, and between a satellite and HAPS in 2027. Through these experiments, NICT will demonstrate compact, ultra-high-speed data communication capabilities and pave the way for the realization of Beyond 5G/6G Non-Terrestrial Networks (NTN).

A team of researchers from YOKOHAMA National University, Japan, have discovered a previously unknown species of marine fungus that can kill harmful, bloom-forming algae.

The new species, Algophthora mediterranea, is a form of microscopic chytrid fungus that can occupy a broad range of hosts, suggesting that chytrid fungi – a diverse group of aquatic fungi – may play a greater role in marine ecosystems than previously thought.

Critically, the fungus was identified as a destructive parasite in a species of algae, Ostreopsis cf. ovata, known to cause toxic blooms that have adverse health effects on humans. The findings are published online in Mycologia on December 15, 2025.

A joint team from UOsaka has uncovered the core principles of the loss maximization in rotor-driven gas-liquid two-phase flows. Performing numerical simulations on the supercomputer "SQUID", they identified the causes as direct collisions between the rotor and the liquid surface and pressure imbalances around the rotor. The findings suggest that, in a resonant state, the enhanced fluid motion is drawn toward the front of the rotor, and the flow instability is intensified behind it. The insights from this research would open the possibility of improving energy efficiency, enhancing reliability and lifespan, and providing new design guidelines for various industrial applications.

An Osaka Metropolitan University-led research team conducted a review that examined the theoretical foundations of Artificial Superintelligence and explored how misaligned AI systems could optimize for wrong objectives, leading to patient harm and systemic failures.

Environmental pollutants such as ozone can damage the internal structure of plants and impair their growth and productivity. Conventional assessments requiring sample processing may not accurately reflect internal damage. A new study highlights the application of a novel ‘optical coherence tomography’ scanner for the non-invasive temporal assessment of live plants exposed to ozone. The technique can aid the timely detection of deficiencies and stress-induced damage, thereby supporting better plant management and improving crop productivity.  

Femtosecond laser-induced periodic surface structures can be used to control thermal conductivity in thin film solids, report researchers from Japan. Their innovative method, which leverages high-speed laser ablation, produces parallel nanoscale grooves with unprecedented throughput that is 1,000 times stronger than conventional approaches, strategically altering phonon scattering in the material. This scalable and semiconductor-ready approach could make it possible to mass-produce thermal engineering structures while maintaining laboratory-level precision.

Road accidents often stem from failing to notice vehicles. A recent study introduced a method for detecting distant vehicles with over twice the accuracy of existing systems. Instead of using road markings, it analyzes the motion of nearby vehicles to estimate the road’s trajectory and vanishing point, capturing distant road areas. By enlarging distant regions, the system can more accurately detect faraway vehicles, thereby enhancing safety by providing distant-vehicle information to drivers and pedestrians.

In a new Nature Physics study, researchers created particle-like so-called “vortex knots” inside chiral nematic liquid crystals, a twisted fluid similar to those used in LCD screens. For the first time, these knots are stable and could be reversibly switched between different knotted forms, using electric pulses to fuse and split them.

Aluminum is prized for being lightweight and strong, but at high temperatures it loses strength. This has limited its use in engines, turbines, and other applications where parts must stay strong under high temperature conditions. Researchers at Nagoya University have developed a method that uses metal 3D printing to create a new aluminum alloy series optimized for high strength and heat resistance. All new alloys use low-cost, abundant elements, and are recycling-friendly, with one variant staying both strong and flexible at 300°C. The study was published in Nature Communications.

【Key Research Achievements】

Demonstration that natural bacteria isolated from amphibian and reptile intestines achieve complete tumor elimination with single administration

Combines direct bacterial killing of cancer cells with immune system activation for comprehensive tumor destruction

Outperforms existing chemotherapy and immunotherapy with no adverse effects on normal tissues

Expected applications across diverse solid tumor types, opening new avenues for cancer treatment