Fiber structures and material science in optical fiber magnetic field sensors.

Magnetic field sensing plays an important role in many fields of scientific research and engineering applications. Benefiting from the advantages of optical fibers, the optical fiber-based magnetic field sensors demonstrate characteristics of light weight, small size, remote controllability, reliable security, and wide dynamic ranges. This paper provides an overview of the basic principles, development, and applications of optical fiber magnetic field sensors.

The Jurassic epiphytic macrolichen reveals the oldest lichen-plant interaction in a Mesozoic forest ecosystem.

Lichens are well known as pioneer organisms or stress-tolerant extremophiles, potentially playing a core role in the early formation of terrestrial ecosystems. Epiphytic macrolichens are known to contribute to the water- and nutrient cycles in forest ecosystem. But due to the scarcity of fossil record, the evolutionary history of epiphytic macrolichens is poorly documented.

An ultraweak mechanical stimuli actuated single electrode triboelectric nanogenerator with high energy conversion efficiency.

Triboelectric nanogenerator (TENG) as a new energy harvester has attracted significant attention due to its excellent output performance and high energy conversion efficiency at low-frequency, small-amplitude and weak-force compared with a traditional electromagnetic generator. Here, an ultraweak mechanical stimuli actuated single electrode triboelectric nanogenerator (UMA-TENG) has been studied with an atomic force microscope. The electrical output and force curve of UMA-TENG were studied at first, as well as the maximum output performance and highest energy conversion efficiency.

Friction-Dominated Carrier Excitation and Transport Mechanism for GaN-Based Direct-Current Triboelectric Nanogenerators.

The semiconductor triboelectric nanogenerator (TENG) based on the tribovoltaic effect has the characteristics of direct current and high current density, but the energy transfer and conversion mechanism is not completely clear. Here, a series of gallium nitride (GaN)-based semiconductor direct-current TENGs (SDC-TENGs) are investigated for clarifying the carrier excitation and transport mechanism. During the friction process, the external output current always flows from GaN to silicon or aluminum, regardless of the direction of the built-in electric field, because of the semiconductor types.

Semiconductor Contact-Electrification-Dominated Tribovoltaic Effect for Ultrahigh Power Generation.

The semiconductor direct-current triboelectric nanogenerator (SDC-TENG) based on the tribovoltaic effect is promising for developing a new semiconductor energy technology with high power density. Here, the first SDC-TENG built using gallium nitride (GaN) and bismuth telluride (Bi Te ) for ultrahigh-power generation is reported. During the friction process, an additional interfacial electric field is formed by continuous contact electrification (CE), and abundant electron-hole pairs are excited and move directionally to form a junction current that is always internally from Bi Te to GaN, regardless of the semiconductor type.

Recent Advances in Optical Fiber Enabled Radiation Sensors.

Optical fibers are being widely utilized as radiation sensors and dosimeters. Benefiting from the rapidly growing optical fiber manufacturing and material engineering, advanced optical fibers have evolved significantly by using functional structures and materials, promoting their detection accuracy and usage scenarios as radiation sensors. This paper summarizes the current development of optical fiber-based radiation sensors.