1：Experimental Design and Method Selection:

The study involved the fabrication of TiO2:Nb nanoantenna arrays using electron beam lithography combined with plasma etching and oxygen plasma ashing processes. The optical properties were characterized with Fourier transform infrared spectroscopy (FTIR).

2：Sample Selection and Data Sources:

The samples were prepared on silicon (001) and borosilicate glass substrates. The TiO2:Nb film was co-sputtered at room temperature with TiO2 ceramic and Nb metallic targets.

3：List of Experimental Equipment and Materials:

Equipment included a sputtering chamber (Shibaura Mechatronics Corporation), Ellipsometry (SENTECH), electron beam lithography (ELIONIX), reactive ion etching (ULVAC), oxygen plasma ashing (Mory PB-600), scanning electron microscopy (SEM, Hitachi), Atomic force microscope (AFM, Bruker Corporation), and Fourier transform infrared spectroscopy (FTIR, Thermo Scientific Nicolet iS50).

4：0). Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: The process involved sputtering deposition, electron beam lithography, development, dry etching with SF6 gas, and oxygen plasma ashing. The samples were then characterized using SEM, AFM, and FTIR.

5：Data Analysis Methods:

The data were analyzed using Finite-Difference Time-Domain method (FDTD) simulations to compare with experimental results.