Analog repeaters dramatically enhance millimeter-wave (mmWave) coverage in mobile networks by overcoming signal blockage, report researchers from Science Tokyo. As demonstrated in a field experiment at Ookayama Campus, low-cost repeaters connected either wirelessly or via optical fiber offer a promising solution for 5G and 6G networks. Both configurations achieved over 1 Gbps throughput and enhanced mmWave signal stability, showing strong potential for practical deployment in urban and high-traffic areas.

Researchers in Japan have developed a needle-type multi-enzyme biosensor that enables real-time monitoring of sucrose levels inside living plants. The sensor revealed daily patterns of sugar transport in strawberry guava and demonstrated that Japanese cedar can absorb sucrose through light-regulated stomata. The device, with its high sensitivity and stability, opens new avenues for studying plant physiology and optimizing agricultural practices through continuous, in vivo tracking of sugar dynamics under natural and controlled conditions.

Magnetic hysteresis loss or iron loss in soft magnetic materials accounts for approximately 30% of energy loss in electric motors. This loss results in significant energy loss globally, representing a pressing environmental concern. However, the origin of iron loss remains elusive despite decades of research. Now, scientists have developed a new physics-based machine-learning approach that automatically identifies the origin of iron loss, establishing a new paradigm for designing efficient soft magnetic materials.

A research team has discovered an electrochemical method that allows highly selective para-position single-carbon insertion into polysubstituted pyrroles. Their approach has important applications in synthetic organic chemistry, especially in the field of pharmaceuticals.

Their work is published in the Journal of the American Chemical Society on July 14.

NIMS has developed a new theory that explains why tunnel magnetoresistance (TMR) —used in magnetic memory and other technologies— oscillates with changes in the thickness of the insulating barrier within a magnetic tunnel junction (MTJ). This oscillation was clearly observed when NIMS recently recorded the world’s highest TMR ratio. Understanding the mechanisms behind this phenomenon is expected to significantly aid in further increasing TMR ratios. This research was published as a letter article in Physical Review B, a journal of the American Physical Society, on June 9, 2025.

A joint research team from Institute of Science Tokyo (Science Tokyo) and Hiroshima University has successfully improved the performance of terahertz-band communication devices using a mechanical tuning technique based on a microactuator.

Terahertz waves exceeding 100 GHz offer the potential to utilize extremely wide frequency bandwidths for communication, and research and development in this field has been accelerating worldwide. In Japan, in addition to ongoing studies in the 300 GHz band, active research in the 150 GHz band has recently gained momentum. However, as the frequency increases, the wavelength becomes shorter, making the impact of unavoidable mechanical fabrication errors more significant. These errors can greatly affect the performance of the communication modules.

To address this challenge, the research team applied a microactuator capable of sub-micrometer precision to terahertz-band components such as the waveguide transitions that connect antennas and chips. This approach aimed to compensate for performance degradation caused by mechanical inaccuracies. A reflective surface inside a waveguide transition was constructed using a flexible conductive membrane, and its position was controlled by the microactuator. As a result, the team demonstrated that the reflection and transmission characteristics of the waveguide transition could be precisely tuned at 250 GHz.