ZrNCl-ZrNBr heterostructure-based UV photodetectors polarization sensitivity study

Through first-principles calculations and quantum transport simulations, this study investigates the polarization sensitivity of ZrNCl-ZrNBr van der Waals heterostructures (vdW) as ultraviolet (UV) photodetectors. While ZrNCl and ZrNBr monolayers show C 3 V symmetry and polarization-dependent photocurrents in the UV range, their response is limited by material symmetry and optical absorption. The ZrNCl-ZrNBr vdWh heterostructure, however, exhibits significantly enhanced optical responsivity due to reduced symmetry and a type II band arrangement, achieving a photocurrent response amplified by up to three orders of magnitude in the 3.5–6.0 eV UV range under zero bias, with a maximum extinction ratio of 180.73. These improvements are attributed to C 1 symmetry-induced polarization dependence and reduced electron-hole recombination. The heterostructure's wide bandgap, self-power capability, and high polarization sensitivity make it a promising candidate for UV photodetection, offering a new theoretical and material basis for advanced photodetector design and understanding of photoelectric phenomena in wide-bandgap semiconductors.