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Terahertz (THz) metamaterial sensor is a newly-developing interdisciplinary technology, which combines the essential characteristics of THz spectroscopy and metamaterials, to obtain better sensitivity for trace detection of the different target analytes. Toroidal dipole resonances show great sensing potential due to their suppression of the radiative loss channel. Here, we found a high-quality planar toroidal dipole resonance in the breaking Chinese Taichi-like ring and then designed a novel polarization-independent terahertz toroidal sensor by combining four Taichi-like rings into a cycle unit. The sensor shows high-sensitivity sensing characteristics for the ultrathin analyte and refractive index. The optimized sensitivity of pure analytes under 4 μm coating thickness can numerically reach 258 GHz/RIU in the corresponding ∼1.345 THz frequency domain, which is much higher than that of previously reported sensors. We further fabricated experimentally the sensor and demonstrated its fascinating polarization-independent characteristics. Finally, it was successfully applied to the low-concentration detection (ranging from 0.0001 mg/mL to 10 mg/mL) of Aβ protein associated with Alzheimer’s disease. Our high-sensitivity polarization-independent THz toroidal dipole sensor would give access to rich applications in label-free biosensing.

The Eastern Kunlun Range in north Tibet, located along the northern margin of the eastern Tethyan orogenic system, records evidence for continental break‐up and ocean development in the Neoproterozoic, Paleozoic‐early Mesozoic subduction and continental collision, Mesozoic intracontinental extension, and Cenozoic contractional deformation. The Kunlun region is marked by active left‐lateral strike‐slip deformation of Kunlun fault system, one of the major intracontinental strike‐slip faults in Tibet that developed in response India‐Asia. To better constrain the tectonic evolution of the Eastern Kunlun Range and the closure of the various Kunlun oceans, we conducted detailed investigation integrating new geologic mapping, geochronology, and whole‐rock geochemistry with a synthesis of existing datasets across north Tibet. The Eastern Kunlun Range experienced three major deformation events in the Neoproterozoic, early Paleozoic, and Late Paleozoic‐early Mesozoic, which were associated with collision of the Proto‐, Paleo‐, and Neo‐Kunlun arcs, respectively. Our new detrital zircon analyses from Mesoproterozoic‐Cenozoic strata constrain stratigraphic age and sediment provenance and highlight the importance of three periods of arc activity. Our stratigraphic synthesis, including new field observations, provides new insights into connections between sediment dispersal and changes in tectonism and paleogeography. Miocene‐to‐present strike‐slip activity on the Kunlun fault and the associated strain pattern can be explained by clockwise rotation of the Kunlun fault and its wall rock as a bookshelf‐fault system, which has been proposed for northern Tibet as a result of distributed north‐south right‐lateral shear. The development of this fault system was facilitated by the presence of a Triassic suture that provided a preexisting weakness. The Eastern Kunlun Range in northern Tibet is located within the interior high‐elevation Tibetan Plateau. Its current morphology and geologic structure reflect Cenozoic faulting related to India‐Asia convergence since the early Cenozoic. Active deformation across the Eastern Kunlun Range reactivates complex older geologic relationships that record prior oceanic subduction and continental collision events. We present field and analytical observations from key sites along the Kunlun and Xiangride Rivers across the Eastern Kunlun Range to establish the pre‐Cenozoic geologic history of this region. Our dating of arc‐related intrusions and sedimentary rocks reveals that three distinct ocean‐closure‐related collisions occurred here over the last billion years. This repeated focused deformation has been reactived most recently in the Cenozoic to for the left‐slip Kunlun fault. The Eastern Kunlun Range, north Tibet, experienced three arc‐collision events in the Proterozoic through MesozoicNew detrital zircon data from Mesoproterozoic‐Cenozoic better constrain their stratigraphic age and provenance in the Kunlun regionThis site of repeated continental collision was reactivated by Cenozoic deformation during India‐Asia convergence

The Mesozoic granodioritic Fenghuangshan pluton is one of a number of intermediate to felsic calc-alkaline plutons responsible for polymetallic mineralization in the middle and lower part of the Yangtze River tectono-magmatic-metallogenic belt. It was intruded into the core of the Fenghuangshan synclinorium of Silurian to Middle Triassic sedimentary strata. In this study of the pluton, we have measured its anisotropy of magnetic susceptibility (AMS) as well as the dimensions and orientations of numerous mafic enclaves. Samples were collected from 37 AMS stations evenly distributed throughout the Fenghuangshan pluton. Twenty-two sites for enclave analysis were selected, and 10-40 enclaves at each site were measured for their orientations and axial ratios. Pluton foliation defined by minerals, enclave geometry, and AMS determinations all define an asymmetric foliation pattern for the pluton. Foliations dip inward along its eastern margin, but dip outward on its western side, suggesting an asymmetric mushroom-like shape of the pluton. The pluton's internal fabrics indicate that it experienced diapiric ascent from an injection center in the western part of the body. The P', T, and axial ratios of oblate enclaves are higher along the pluton's eastern margin, suggesting that magma flow was to the ENE during the final ballooning stage of emplacement. Crystallization ages of the Fenghuangshan and other Mesozoic plutons in the region range from ∼142.8 Ma to ∼151.8 Ma. Our interpretation that the plutons were emplaced during D2 regional deformation helps to constrain the ages of earlier Tethyan-related D1 and late Western Pacific-related D3 tectonism.