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.