1D Van Der Waals Superlattices for Polarization‐Sensitive Photodetectors

Abstract The ability to detect polarimetric information of light over a broad spectra range is central to practical optoelectronic applications and has been successfully demonstrated with photodetectors of low‐symmetry 2D van der Waals materials (vdWMs). However, polarization sensitivity within such a photodetectors remains elusive due to the limited diversity. To address this challenge, an approach is proposed by transforms 2D Lead iodine (PbI2) into 1D superlattice microwires (SLMs) through a solution‐phase antisolvent diffusion method. This structural shifting enables the creation of low‐symmetry crystal characteristics, a well‐defined geometric microcavity structure, and an increased bandgap, which collectively confer anisotropic waveguide properties across visible and near‐infrared wavelengths. By integrating PbI2 SLMs with isotropic 2D vdWMs, that waveguide‐integrated photodetectors are demonstrated capable of polarization detection, achieving linear dichroism ratio (LDR) values of 1.66 at 405 nm for PbI2 photodetectors and 1.73 at 785 nm for WSe2 photodetectors. This paradigm‐shifting strategy enables polarimetric information detection using isotropic vdWMs and advances the development of next‐generation polarization‐resolved optoelectronic devices.