(Phys.org) —Traditional three-dimensional (3-D) plasmonic metamaterials with metallic structures – artificial materials that exploit coherent delocalized electron oscillations known as surface plasmons produced from the interaction of light with metal-dielectric materials – exhibit unique electromagnetic properties not found in natural materials, such as extraordinary transmission beyond the diffraction limit, efficient light-harvesting ability, plasmonic color filtering, and the ability to control the reflection or transmission direction of a light beam. However, they are difficult to fabricate, have a narrow usable bandwidth due to their resonant character, and exhibit low optical efficiency due to the inherent metal absorption. While two-dimensional metasurface structures have been proposed in an attempt to address these functional limitations, they still require complex designs and sophisticated fabrication procedures.
- Compact reflective mirrors for laser cavities where the polarized output is required to meet the coherence for optical communication or laser interference
- Diffractive gratings in optical spectrometers, where the TM diffraction efficiency is stably high in a wide waveband with high angle resolution since the pith is only several hundred nanometers, which has several advantages: as a reflection element it provides a range of benefits, such as allowing the controlling circuit to be placed below the reflective surface, and more advanced integrated circuit technology becomes available when the substrate materials are not limited by their opaqueness; and a folded light path wherein the input and output light beam share the same physical space, which offers a desirable compact arrangement
- As a novel plasmonic beam splitter, it can also be implemented in integrated optics devices for communication: TM light is diffracted into one waveguide and TE light is reflected into the other, allowing the two beams to be manipulated for further use