Multiresponse reconfigurable free-standing cascaded plasmonic grating with strong unidirectional guiding properties

A multiresponse plasmonic structure constructed by integrating two stacked plasmonic gratings with reconfigurable properties is presented. The integration of the structure with a micro-electro-mechanical (MEMS) device would allow for control of the He-Ne laser wavelength (633 nm) electromagnetic plane wave interaction with the structure. By adjusting only a relative horizontal shift between two stacked silver gratings, it is possible to achieve either high transmission (80%), reflection (98%), or high absorption (>98%) caused by the redirecting of the normally incident wave into a horizontal direction inside the structure. A thorough mode analysis was conducted, and the structure's response to the incident light was analyzed. Such reconfigurable plasmonic-photonic structures can find their applications in various optical routing and guiding devices such as optical switches, filters, multiplexers, or beam splitters, increasing the capacity of optical communication systems.