CAJ | 학술논문

各向异性超材料可以控制太赫兹波的偏振态，实现入射太赫兹波的偏振转换。为了获得非手性各向异性超材料的透射响应与本征偏振复透射系数的关系及其入射偏振依赖性，在太赫兹时域光谱系统中测量了等臂长 L 形结构超材料在不同偏振角下的正入射透射谱，获得并分析了透射太赫兹波的偏振转换率和偏振态，所得结果与基于琼斯矩阵和坐标变换计算的结果一致。在0.7 THz~1.3 THz频率范围内可实现约20%的偏振态能量转换效率。在 L结构和双 L结构的偏振转换透射谱中分别观察到了宽带响应和多频共振响应，表明结构改变对太赫兹波透过特性的敏感性和可操控性。所得到的结果可用于太赫兹功能器件的设计、表征和优化。
각향이성초재료가이공제태혁자파적편진태，실현입사태혁자파적편진전환。위료획득비수성각향이성초재료적투사향응여본정편진복투사계수적관계급기입사편진의뢰성，재태혁자시역광보계통중측량료등비장 L 형결구초재료재불동편진각하적정입사투사보，획득병분석료투사태혁자파적편진전환솔화편진태，소득결과여기우경사구진화좌표변환계산적결과일치。재0.7 THz~1.3 THz빈솔범위내가실현약20%적편진태능량전환효솔。재 L결구화쌍 L결구적편진전환투사보중분별관찰도료관대향응화다빈공진향응，표명결구개변대태혁자파투과특성적민감성화가조공성。소득도적결과가용우태혁자공능기건적설계、표정화우화。
Anisotropic metamaterials can be utilized to manipulate the polarization states of terahertz waves, and realize the polarization conversion. In order to obtain the dependence of transmission properties of achiral anisotropic metamaterials on the complex transmission coefficients of eigenmodes and incident polarization angles, transmission spectra of L-shaped metamaterials at different polarization angles are measured using terahertz time-domain spectroscopy. Consistent results are obtained through analytical calculation based on the Jones matrix and coordinate transformation. The polarization conversion rates and polarization states of transmitted terahertz waves are obtained and analyzed by the complex transmission coefficients of eigenmodes. A flat polarization conversion efficiency of about 20% is demonstrated in the frequency range 0.7 THz-1.3 THz. In addition, the cross-polarized transmission spectrum of L-shaped metamaterials is compared with that of double L-shaped metamaterials. Broadband and multiband responses are observed, respectively. The results can be used for design, characterization and optimization of various terahertz functional devices.