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Narrowband photodetectors have attracted considerable attention owing to their ability to suppress interference from nontarget wavelengths. However, operation of sensitive narrowband detection usually requires a high driving voltage, which leads to high power consumption and severe degradation of device performance. In this study, a narrowband 1050 nm photodetector with high sensitivity and excellent wavelength selectivity was realized using a simple ${p}$ -type Si Schottky junction. The device exhibited a high responsivity of 810 mA/W and a large linear dynamic range of 128 dB at zero bias. At a low bias voltage of −3 V, its external quantum efficiency increased to ${6}.{9}\times {10} ^{{3}}$ %, with a full width at half maximum of approximately 74 nm. This outstanding device performance can be ascribed to the unique geometry of dual Ti /Ag Schottky electrode and the gain mechanism derived from the large transit-time difference between the photogenerated electrons and holes. This study opens new avenues for the development of highly sensitive narrowband photodetectors with low driving voltages in the future.

CyprideaBosquet, 1852 is a non-marine ostracod genus of the Superfamily Cypridoidea, and the extinct Family Cyprideidae, which achieved high diversity in the Early Cretaceous. This genus plays an important role in the subdivision and correlation of strata, as well as in paleogeographic and paleoclimatic studies. Cyprideaspecies are remarkably abundant and diverse, and are extensively distributed across East Asia. However, the lowermost occurrence of Cyprideaspecies (LOOC) in East Asia is still being debated, varying from the Upper Jurassic to Lower Cretaceous. Here, we aim to conduct a preliminary investigation of the Cypridea-bearing strata of East Asia (China, Mongolia, Korea and Japan), and attempt to update the strata correlation, based on new progress of the ostracod correlations, as well as the progress of other research methods on the relative Jurassic/Cretaceous (J/K) strata of these areas. Results show that the LOOCs in most basins of East Asia are documented in Lower Cretaceous (∼Berriasian) strata. However, Cyprideaspecies are extremely rare near the J/K boundary interval but flourish until Valanginian–Hauterivian in most basins of East Asia. Therefore, we propose that the LOOC in each corresponding basin of East Asia can be used as an auxiliary marker of the non-marine J/K boundary. Cyprideaspecies may have travelled first from Africa (Kimmeridgian) to Europe (J/K period), and then East Asia (Early Cretaceous), which resulted in the LOOC in East Asia later than in the other continents.