Wave vector filter based on surface and Tamm plasmon polaritons.

This study proposes a wave vector filter leveraging coupling-induced transparency (CIT) between surface plasmon polaritons (SPPs) and Tamm plasmon polaritons (TPPs) to enable simultaneous wavelength and incident-angle selection, overcoming conventional optical filters' inability to control both parameters. By synergizing the wave vector selectivity of SPPs with the low-loss field enhancement of TPPs, the device achieves efficient spectral-angular filtering in the short-wave infrared regime. Structural optimization of silver gratings and Ag/distributed Bragg reflector (DBR) layers yields a 60% transmission peak at 2.08 μm. The transmission intensity decreases by an order of magnitude with 0.2° angular deviation, demonstrating exceptional wave vector selectivity. Experimental validation confirms the angle-wavelength dual-selectivity mechanism, showing strong agreement with theoretical models. This work addresses critical challenges in multi-parameter photonic control, offering a breakthrough for hyperspectral imaging, multi-channel sensing, and on-chip nonlinear photonic systems. The CIT-based platform provides a novel design paradigm, to the best of our knowledge, for advanced photonic devices requiring joint spectral-spatial resolution.