Split-disk metamaterial with tunable polarization ratio for optical logic operation application

Terahertz (THz) metamaterials hold promise for advanced communication and sensing applications, yet achieving high polarization selectivity and functional integration remains challenging. Here, we propose a tunable split-disk resonator (SDR) to address these challenges. This is an excellent demonstration of THz metamaterial that achieves both ultra-high polarization ratio and programmable logic gates solely through geometric tuning, without relying on phase-change materials, external biasing, or hybrid substrates. By synergistically adjusting the SDR height (h) and rotation angle (θ), the structure achieves the high polarization ratio (PR > 3579) at 0.79 THz under the conditions of h = 5 µm and θ = 180°, outperforming prior metamaterials by more than two orders of magnitude. Furthermore, with fixed 90°, SDR devices enable polarization-state encoding for THz logic operations, realizing reconfigurable inverting, XNOR, and buffer gates at 0.60 THz, 0.66 THz, and 0.73 THz, respectively. Numerical simulations reveal that logic functionality arises from transmission intensity thresholds (50 %) defined by structural parameters and polarization inputs. This work pioneers a new approach for integrating photonic logic and polarization filtering in a single THz metamaterial, offering a reconfigurable and fabrication-ready route toward all-optical computing systems.