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Polarization‐sensitive photodetectors can simultaneously sense the polarization states and intensity of light. Traditional polarimeters integrate photodetectors with complex and bulky optical systems such as polarizers and waveplates, which can not meet the current demand of on‐chip polarization photonic devices. This work has demonstrated a full linear polarization polarimeter based on two independent ReS2 nanobelt devices vertically stacked with a designed twist angle. The device achieves a high responsivity (959 A W−1) without applying an external gate voltage. In addition, the ReS2 nanobelt photodetector displays a strong polarization‐sensitive photoresponse with a linear dichroic ratio of 1.72 at 665 nm. By utilizing those two vertically stacked nanobelt devices, the linear polarization states of the incident light can be distinguished in a wide range of wavelengths from 590 to 800 nm. This study provides a simple route for future polarization‐sensitive optoelectronic devices. [ABSTRACT FROM AUTHOR]

Sb2S3 solar cells are lagging behind conventional thin-film solar cells such as silicon solar cells and cadmium telluride solar cells in the power conversion efficiency (PCE). One of the most prominent problems is that the carrier concentration of Sb2S3 is relatively low. In order to increase the carrier concentration, elemental Cu was doped into Sb2S3 film by radio-frequency (RF) magnetron sputtering. We proved that Cu was doped into Sb2S3 films and mainly anchored with sulfur in the form of copper chalcogenide species at the surface and grain boundaries of Sb2S3. The doping of Cu essentially affects the physical and electrical properties of RF-sputtered Sb2S3 films such as the optical band gap, crystallinity, chemical composition, morphology, and carrier concentration. Specially, the electronic carrier concentration is remarkably increased from 6.28 × 109 to 6.06 × 1010 cm−3 and the Fermi level is also significantly uplifted after prudent doping with Cu. Planar solar cells based on RF-sputtered Cu-doped Sb2S3 absorber deliver an increased PCE of 1.13% and show good stability. This research proves that doping of Cu is an alternative and effective way to improve the electronic property of Sb2S3 films and enhance the performance of Sb2S3 solar cells. [ABSTRACT FROM AUTHOR]