本研究探討兆赫茲波段MIM結構超材料頻率選擇器，特別分析中間層材料在該結構的實驗可行性與電磁特性影響。藉由理論分析、數值模擬及實驗量測，以具雙折射特性的Y-cut鈮酸鋰(LiNbO₃)作為介電層材料，設計方形環與方形裂環兩種結構，驗證TE與TM偏振模式下的頻譜差異。
結果顯示，Y-cut鈮酸鋰MIM結構展現明顯的偏振依賴性，且實驗與模擬數據具有相近的共振頻率與吸收峰。電磁場與表面電流模擬進一步揭示各結構在共振時的能量集中與分布特性。
此外，研究也深入分析材料選擇與製程挑戰，最終確認Y-cut鈮酸鋰為理想的中間層材料，成功實現高效的THz頻率選擇與吸收。整體而言，本研究驗證雙折射介電材料在THz超材料設計的應用價值，並提供製程經驗與設計依據，為未來多功能、高靈敏度元件開發奠定基礎。

This study investigates metal-insulator-metal (MIM) metamaterial frequency selectors operating in the terahertz (THz) range, focusing on the effects of the dielectric intermediate layer on device feasibility and electromagnetic properties. Through theoretical analysis, numerical simulations, and experimental measurements, Y-cut lithium niobate (LiNbO₃), a birefringent dielectric, was selected as the middle layer material. Two meta structures, the Square Ring and Square Split Ring, were analyzed to compare their spectral responses under TE and TM polarization.
The results demonstrate clear polarization-dependent behavior in the Y-cut LiNbO₃ MIM structures, with experimental data closely matched with simulation results regarding resonance frequencies and absorption peaks. Field and surface current simulations further illustrate energy localization and distribution characteristics at resonance.
Additionally, the study addresses material selection and fabrication challenges, confirming Y-cut LiNbO₃ as an ideal dielectric material for achieving efficient frequency selection and absorption in the THz band. Overall, this research validates the importance of birefringent dielectrics in THz metamaterial design, providing practical fabrication experience and design insights for developing future multifunctional and high-sensitivity THz devices.

[1] X. Fu, Y. Liu, Q. Chen, Y. Fu, and T. J. Cui, "Applications of terahertz spectroscopy in the detection and recognition of substances," Frontiers in Physics, vol. 10, p. 869537, 2022.
[2] V. Veselago, "The electrodynamics of substances with simultaneously negative values of and," Usp. fiz. nauk, vol. 92, no. 3, pp. 517-526, 1967.
[3] D. R. Smith, W. J. Padilla, D. Vier, S. C. Nemat-Nasser, and S. Schultz, "Composite medium with simultaneously negative permeability and permittivity," Physical review letters, vol. 84, no. 18, p. 4184, 2000.
[4] H. Tao, N. I. Landy, C. M. Bingham, X. Zhang, R. D. Averitt, and W. J. Padilla, "A metamaterial absorber for the terahertz regime: design, fabrication and characterization," Optics express, vol. 16, no. 10, pp. 7181-7188, 2008.
[5] H. Zhu, Y. Zhang, L. Ye, Y. Li, Z. Dang, R. Xu, and B. Yan, "A high Q-factor metamaterial absorber and its refractive index sensing characteristics," IEEE Transactions on Microwave Theory and Techniques, vol. 70, no. 12, pp. 5383-5391, 2022.
[6] B. Choudhury and R. Jha, "A review of metamaterial invisibility cloaks," Computers, Materials & Continua, vol. 33, no. 3, pp. 275-303, 2013.
[7] M. Pan, Y. Fu, M. Zheng, H. Chen, Y. Zang, H. Duan, Q. Li, M. Qiu, and Y. Hu, "Dielectric metalens for miniaturized imaging systems: progress and challenges," Light: Science & Applications, vol. 11, no. 1, p. 195, 2022.
[8] Z. Zheng, Y. Luo, H. Yang, Z. Yi, J. Zhang, Q. Song, W. Yang, C. Liu, X. Wu, and P. Wu, "Thermal tuning of terahertz metamaterial absorber properties based on VO 2," Physical chemistry chemical physics, vol. 24, no. 15, pp. 8846-8853, 2022.
[9] A. Ma, R. Zhong, Z. Wu, Y. Wang, L. Yang, Z. Liang, Z. Fang, and S. Liu, "Ultrasensitive THz sensor based on centrosymmetric F-shaped metamaterial resonators," Frontiers in Physics, vol. 8, p. 584639, 2020.
[10] Y. Zhang, Y. Shi, and C.-H. Liang, "Broadband tunable graphene-based metamaterial absorber," Optical materials express, vol. 6, no. 9, pp. 3036-3044, 2016.
[11] Y. Zhang, Y. Feng, B. Zhu, J. Zhao, and T. Jiang, "Graphene based tunable metamaterial absorber and polarization modulation in terahertz frequency," Optics express, vol. 22, no. 19, pp. 22743-22752, 2014.
[12] Y. Tan, Y. Qi, X. Ding, W. Guan, and B. Luo, "Tunable continuously bound states for enhanced circular dichroism in graphene-enhanced metasurfaces," Physica Scripta, vol. 100, no. 4, p. 045551, 2025.
[13] Y.-S. Lin, J. Dai, Z. Zeng, and B.-R. Yang, "Metasurface color filters using aluminum and lithium niobate configurations," Nanoscale Research Letters, vol. 15, no. 1, p. 77, 2020.
[14] A. Weiss, C. Frydendahl, J. Bar-David, R. Zektzer, E. Edrei, J. Engelberg, N. Mazurski, B. Desiatov, and U. Levy, "Tunable metasurface using thin-film lithium niobate in the telecom regime," Acs Photonics, vol. 9, no. 2, pp. 605-612, 2022.
[15] X. Yu, F. Li, T. Lang, J. Qin, and X. Ma, "Ultrasensitive tunable terahertz lithium niobate metasurface sensing based on bound states in the continuum," Photonics Research, vol. 11, no. 12, pp. 2168-2178, 2023.
[16] N. W. Ashcroft and N. D. Mermin, Solid State Physics. Philadelphia: Saunders College, 1976.
[17] R. Singh, E. Smirnova, A. J. Taylor, J. F. O’Hara, and W. Zhang, "Optically thin terahertz metamaterials," Optics express, vol. 16, no. 9, pp. 6537-6543, 2008.
[18] A. Yariv, "Optical electronics in modern communications," (No Title), 1997.
[19] H. Kocer, S. Butun, Z. Li, and K. Aydin, "Reduced near-infrared absorption using ultra-thin lossy metals in Fabry-Perot cavities," Scientific reports, vol. 5, no. 1, p. 8157, 2015.
[20] H.-T. Chen, "Interference theory of metamaterial perfect absorbers," Optics express, vol. 20, no. 7, pp. 7165-7172, 2012.
[21] X. Chao, Y. Xu, F. Huang, and Z. Chen, "A high-quality broadband tunable terahertz metamaterial absorber based on graphene," Journal of Physics D: Applied Physics, vol. 57, no. 7, p. 075106, 2023.
[22] L. Cong, S. Tan, R. Yahiaoui, F. Yan, W. Zhang, and R. Singh, "Experimental demonstration of ultrasensitive sensing with terahertz metamaterial absorbers: A comparison with the metasurfaces," Applied Physics Letters, vol. 106, no. 3, 2015.
[23] R. Weis and T. Gaylord, "Lithium niobate: Summary of physical properties and crystal structure," Applied Physics A, vol. 37, pp. 191-203, 1985.
[24] C. Wang, M. Zhang, B. Stern, M. Lipson, and M. Lončar, "Nanophotonic lithium niobate electro-optic modulators," Optics express, vol. 26, no. 2, pp. 1547-1555, 2018.
[25] C. Wang, M. Zhang, X. Chen, M. Bertrand, A. Shams-Ansari, S. Chandrasekhar, P. Winzer, and M. Lončar, "Integrated lithium niobate electro-optic modulators operating at CMOS-compatible voltages," Nature, vol. 562, no. 7725, pp. 101-104, 2018.
[26] I. Shoji, T. Kondo, A. Kitamoto, M. Shirane, and R. Ito, "Absolute scale of second-order nonlinear-optical coefficients," Journal of the Optical Society of America B, vol. 14, no. 9, pp. 2268-2294, 1997.
[27] G. Poberaj, H. Hu, W. Sohler, and P. Guenter, "Lithium niobate on insulator (LNOI) for micro‐photonic devices," Laser & photonics reviews, vol. 6, no. 4, pp. 488-503, 2012.
[28] L. Wu, X. Zhang, Y. Fu, Z. Xu, X. Ding, and J. Yao, "Tuning the dielectric properties of LiNbO3 based interdigitated electrode metastructure in the terahertz range," Results in Physics, vol. 24, p. 104120, 2021.
[29] Z. Wang and Z. Zhang, "Electron beam evaporation deposition," Advanced nano deposition methods, pp. 33-58, 2016.
[30] I. KemLab, "APOL-LO 3200 Series Negative Photoresist Technical Data Sheet," Phoenix,AZ,USA.
[31] M. J. Madou, Fundamentals of microfabrication: the science of miniaturization. CRC press, 2018.
[32] W. W. Flack, H.-A. Nguyen, and E. S. Capsuto, "Characterization of a novel photoresist redistribution material for advanced packaging applications," in Advances in Resist Technology and Processing XIX, 2002, vol. 4690: SPIE, pp. 1203-1216.
[33] J. J. Yu, B. Singh, and A. T. Hui, "Method of using controlled resist footing on silicon nitride substrate for smaller spacing of integrated circuit device features," ed: Google Patents, 2003.
[34] S. S. Cohen, "Electrical Properties of Post‐annealed Thin SiO2 Films," Journal of The Electrochemical Society, vol. 130, no. 4, p. 929, 1983.
[35] F. Grigoriev, E. Katkova, A. Sulimov, V. Sulimov, and A. Tikhonravov, "Annealing of deposited SiO2 thin films: full-atomistic simulation results," Optical Materials Express, vol. 6, no. 12, pp. 3960-3966, 2016.
[36] Y. Jiang, Y. Ji, H. Liu, D. Liu, L. Wang, C. Jiang, Y. Yang, and D. Chen, "Insights into effects of thermal annealing on optical properties of SiO2 films," in 6th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, 2012, vol. 8416: SPIE, pp. 106-110.
[37] C. Viana, N. Morimoto, and O. Bonnaud, "Annealing effects in the PECVD SiO2 thin films deposited using TEOS, Ar and O2 mixture," Microelectronics Reliability, vol. 40, no. 4-5, pp. 613-616, 2000.
[38] B. Grześkiewicz, A. Sierakowski, J. Marczewski, N. Pałka, and E. Wolarz, "SU-8 based planar metamaterials with fourfold symmetry as selective terahertz absorbers," Opto-Electronics Review, vol. 26, no. 4, pp. 329-337, 2018.
[39] D. Grbovic, F. Alves, B. Kearney, B. Waxer, R. Perez, and G. Omictin, "Metal-organic hybrid resonant terahertz absorbers with SU-8 photoresist dielectric layer," Journal of Micro/Nanolithography, MEMS, and MOEMS, vol. 12, no. 4, pp. 041204-041204, 2013.
[40] Z. Alipour, S. Mirzaei, and M. Fardmanesh, "Design, Fabrication and Characterization of Wide-Band Metamaterial Absorber for THz Im-aging. 2023, 5, x," ed: s Note: MDPI stays neu-tral with regard to jurisdictional claims in …, 2023.
[41] 胡之厅, 程纪伟, 杜磊, 朱钰方, 张家振, 徐煌, 刘锋, and 陈刚, "Theoretical study on the far-infrared perfect absorbers with SU8 based multilayered metamaterial structure," Journal of Infrared and Millimeter Waves, vol. 38, no. 1, pp. 21-26, 2019.
[42] M. Zhong, S. J. Liu, B. L. Xu, J. Wang, and H. Q. Huang, "Design and measuring of a tunable hybrid metamaterial absorber for terahertz frequencies," Optical Materials, vol. 78, pp. 1-7, 2018.
[43] X. Lei, Y. Li, S. Huo, Z. Sun, H. Yu, L. Fang, S. Xu, B. Li, M. Wang, and E. Li, "Design and analysis of a novel compact metamaterial absorber based on double-layer ITO resistive film for improving signal integrity," IEEE Access, vol. 10, pp. 24067-24079, 2022.
[44] J. Dong, Y. Ma, and M. Wang, "An ultrawideband miniaturized ultrathin flexible metamaterial absorber using lightweight ITO film," IEEE Antennas and Wireless Propagation Letters, vol. 22, no. 12, pp. 2970-2974, 2023.
[45] S. Lai, Y. Guo, G. Liu, Y. Liu, C. Fu, H. Chang, Y. Wu, and W. Gu, "A high-performance ultra-broadband transparent absorber with a patterned ITO metasurface," IEEE Photonics Journal, vol. 14, no. 3, pp. 1-7, 2022.
[46] Y. Zhang, L. Zhang, X. Dong, and L. Zheng, "Design of a broadband mid-to-far infrared metamaterial absorber," in International Conference on Information Optics and Optoelectronics Technology (CIOT 2024), 2025, vol. 13683: SPIE, pp. 23-29.
[47] Z. Li, J. Jia, W. Jiang, W. Ou, B. Wang, X. Peng, H. Wu, and Q. Zhao, "Substrate-free silicon nitride films for metamaterial absorbers designed with Lorentz quadratic model," Materials Science in Semiconductor Processing, vol. 169, p. 107868, 2024.
[48] Z. Zhou, Y. Chen, Y. Tian, J. Liang, and W. Yang, "Ultra-broadband metamaterial perfect solar absorber with polarization-independent and large incident angle-insensitive," Optics & Laser Technology, vol. 156, p. 108591, 2022.