Non-Hermitian reconstruction of hybridized hyperbolic shear polaritons

RESUMO

Hyperbolic shear polaritons (HShPs) represent a distinctive class of anisotropic polaritonic states that enable directional subwavelength light manipulation through asymmetric momentum-space dispersion, while their control in twisted systems has so far relied mainly on geometric and spectral parameters. Here, we introduce non-Hermitian dissipation as an additional degree of freedom for tuning HShPs in twisted van der Waals heterostructures. In twisted {\alpha}-MoO3/{\alpha}-V2O5 heterostructures with closely matched isofrequency contours but distinct dielectric losses, dissipation modifies the complex hybrid polaritonic states and thereby tunes the resulting momentum-space and real-space asymmetry. Near-field infrared imaging combined with analytical modeling and full-wave simulations reveals the evolution of the shear response with twist angle, excitation frequency, layer thickness, and substrate dielectric environment. The interplay between material dissipation and dielectric screening enables continuous regulation of the shear degree and reversible switching between shear-off and shear-on states. Furthermore, we demonstrate a proof-of-concept binary-state encoding scheme based on dissipation-controlled shear-state switching. Our work identifies non-Hermitian dissipation as an additional control parameter in twisted polaritonic systems, expanding the available design space for reconfigurable mid-infrared nanophotonics.