中文摘要：

研究了矩形块微纳结构吸收材料在中远红外波段的光学偏振吸收特性.该吸收材料由金属阵列-电介质层-金属膜组成,在2.0 μm～5.0 μm波长具有双波长谐振吸收效应,其理论吸收率大于80％.模拟计算和实验测试表明,该吸收材料的短波吸收峰值与矩形块长轴方向入射偏振光的3阶谐振响应对应,而长波吸收峰值与短轴方向基模谐振响应对应.实验制备了矩形阵列光吸收器并测试了它的的光学特性,结果表明：该吸收器结构在两个偏振方向的等效磁导率系数满足Lorentz模型,等效磁导率谱线虚部峰值波长与吸收谐振波长相对应,表明这种吸收材料的偏振吸收与入射电磁波的磁谐振响应有关.研究结果揭示了微纳结构吸收器的双波长频谱吸收机理,有助于实现特定波长生物传感器及光电探测器的设计.

英文摘要：

The polarization-dependent absorption of the rectangular-block perfect absorber metamaterials in mid-infrared regime was investigated theoretically and numerically.The rectangularshaped nanostructure absorber consisting of metal-dielectric-metal layers has dual-band resonant absorption spectrum at infrared wavelength of 2.0-5.0 μm and its absorptivity is more than 80％.The simulation results indicate that the dual-band resonance spectra of the materials are attributed to the third order resonance mode and the fundamental mode of the perpendicular polarized incident electronic field.A rectangle array optical absorber was developed and its optical properties were measured.The test results show that equivalent permeability of the absorber in two polarized configurations is satisfied the Lorentz model and the imaginary parts of the permeability agree well with the resonance absorption wavelengths,which indicates that the polarization absorption of the materials is depended on the magnetic resonance induced by the incident wave.These results point out that the dual-band resonant absorption mechanism of the nanostructure absorber is conductive to design of biosensors and photoelectric detectors in special wavelengths.