Mechanism of optical unidirectional transmission in subwavelength dual-metal gratings

作者：Gao, H.^*; Zheng, Z. Y.; Hao, H. Y.; Dong, A. G.; Fan, Z. J.; Liu, D. H.

来源：Applied Physics B: Lasers and Optics , 2014, 114(3): 401-406.

DOI：10.1007/s00340-013-5533-z

• EXTRAORDINARY TRANSMISSION
• NONSYMMETRIC GRATINGS
• DIODE
• LIGHT
• SLIT

The mechanism of optical unidirectional (OUD) transmission in parallel subwavelength dual-metal gratings was investigated. It was found that this kind of OUD phenomenon originates from the coupling of the surface plasmon polaritons (SPPs) between the front grating and a layer of metal film which replaces the rear grating. The higher the intensity of the coupled SPPs at the entrances of the rear grating, the higher the transmittance can be achieved. Basing on this property, an effective OUD example was achieved by exploring the intensity difference at the entrances of the rear gratings between the two incidences of opposite directions. In this kind of OUD, the positive transmittance can exceed 80 % and the difference between the transmittances of the two opposite directions can be as large as 63 %. The detailed design process was also presented.

• 出版日期2014-3
• 单位中国地质大学（北京）; 北京师范大学