Wireless NIR Four-Quadrant Detector System Based on PbS Collodial Quantum Dots

Here, we first propose a self-powered near-infrared (NIR) four-quadrant detector (4-QD) based on PbS colloidal quantum dots (CQDs) by using a novel functional ligand customization (FLC) method. The 4-QD exhibits high uniformity and excellent NIR photoresponse in the range of 700-1400 nm with a responsivity up to 0.43 A/W, response time of $42~\mu $ s and linear dynamic range (LDR) approaching 90 dB in the self-powered model. Notably, the PbS CQDs 4-QD based wireless NIR detector system was successfully built to monitor the NIR laser position in real time. The result suggests a pathway on fabrication of CQDs 4-QDs for real-time wireless NIR laser positioning.