Toggle light / dark theme

Polarization is one of the fundamental characteristics of electromagnetic waves. It can convey valuable vector information in sensitive measurements and signal transmission, which is a promising technology for various fields such as environmental monitoring, biomedical sciences, and marine exploration. Particularly in the terahertz frequency range, traditional device design methods and structures can only achieve limited performance. Designing efficient modulator devices for high-bandwidth terahertz waves presents a significant challenge.

Researchers led by Prof. Liang Wu at Tianjin University (TJU), China, have been conducting experiments in the field of all-dielectric metamaterials, specifically focusing on utilizing these materials and their to achieve effective broadband polarization conversion in the terahertz frequency range.

They propose a cross-shaped microstructure metamaterial for achieving cross-polarization conversion and linear-to-circular polarization conversion in the terahertz frequency range. The study, titled “An all-silicon design of a high-efficiency broadband transmissive terahertz polarization convertor,” was published in Frontiers of Optoelectronics.

Non-personalized content and ads are influenced by things like the content you’re currently viewing and your location (ad serving is based on general location). Personalized content and ads can also include things like video recommendations, a customized YouTube homepage, and tailored ads based on past activity, like the videos you watch and the things you search for on YouTube. We also use cookies and data to tailor the experience to be age-appropriate, if relevant.

Select “More options” to see additional information, including details about managing your privacy settings. You can also visit g.co/privacytools at any time.

During the most recent excavations, archaeologists stumbled on a system of secret underground passageways. They found six intersecting tunnels that functioned as a hidden transportation network.

A photo shows a partial map of the passageways. Other photos show a tunnel entrance and a view inside the well-preserved arched tunnels.

Archaeologists said the tunnels were between about 5 feet and about 20 feet down. Inside, the tunnels were between 3 feet and 6 feet tall and roughly 4 feet wide. Several tunnels passed under the city’s defensive walls and opened to the outside.

It was just this week that we told you about Unitree’s latest quadruped robot, the B2. Well, the Chinese company has also announced its first-ever humanoid bipedal robot, the Unitree H1.

With a planned price tag of under US$90,000, the H1 is intended to rival other humanoid bots such as those made by Tesla, Figure and Agility Robotics. As far as basic specs go, it stands 1,805 mm tall (71 in), weighs about 47 kg (104 lb) and can carry a payload of up to 30 kg (66 lb).

Joints in the hip, knee and ankle give each leg a total of five degrees of freedom, while joints in the shoulder and elbow give each arm a total of four degrees. Unitree’s own M107 motors deliver 360 Nm (266 lb ft) of torque at each joint. Flexible fingers are reportedly in the works.