Anisotropic MoTe ₂ /NbSe ₂ Interface-Engineered Vertical Heterojunction for Broadband and High-Performance Polarized Photodetection

With the rapid development of emerging technologies, polarized light detection─a key direction in optoelectronics─plays an irreplaceable role in numerous cutting-edge applications while facing increasingly urgent demands for integration and high performance. Owing to their unique merits, two-dimensional (2D) materials have become ideal candidates for constructing polarized photodetectors, making 2D polarized photodetectors a highly promising research direction. A critical challenge in current 2D polarized photodetectors lies in simultaneously optimizing responsivity, bandwidth, and polarization resolution, which is severely constrained by the limited availability of high-performance anisotropic materials. To overcome this limitation, we present a paradigm shift by realizing high-performance polarized detection using intrinsically isotropic hexagonal materials─MoTe2 and semimetallic NbSe2─thereby decoupling polarization sensitivity from crystallographic anisotropy. Unlike traditional approaches, we exploit interfacial symmetry breaking to induce strong polarization sensitivity in the vertically stacked Au/MoTe2/NbSe2 heterojunction. Operating in the self-powered mode, the vertical heterojunction achieves an excellent responsivity of 907 mA/W at a wavelength of 660 nm, with a response wavelength extendable to 1550 nm. Compared with the Au/MoTe2/1T′-MoTe2 vertical heterojunction, the responsivity is enhanced by nearly 11 times. Meanwhile, the in-plane anisotropy of the MoTe2/NbSe2 interface endows the heterojunction with strong polarization characteristics, enabling it to exhibit outstanding polarization-dependent photoresponse across the full wavelength range of 405 to 1550 nm, with a maximum polarization ratio as high as 24.9. This work proves that “interfacial symmetry engineering” can liberate polarized photodetectors from the constraints of low-symmetry crystals, offering a viable pathway to design next-generation logic-free optoelectronic systems.