L-shaped metasurface for both the linear and circular polarization conversions

Abstract

A new type of optical polarization converter based on the L-shaped gold nanoantenna array supercell has been presented, which is suitable for both circular and X/Y linear polarization conversion simultaneously. Both the amplitude and phase of transmitted cross-polarization light can be modulated precisely by changing the lengths and widths of the L-shaped nanoantenna units. For circular or X/Y linear polarization incident lights, the corresponding cross-polarized lights can be obtained in the transmitted lights, and the corresponding bending angles of the cross-polarized lights can be modulated by the structures and the incident angles according to the generalized Snell’s law. The multi-spectral characteristics have also been investigated, in which the operating bandwidth of the designed optical polarization converter is 450 nm (in the range of 750 ∼ 1200 nm).

Using reflection and transmission coefficients to retrieve surface parameters for an anisotropic metascreen: With a discussion on conversion between TE and TM polarizations

“…If the anisotropic terms are zero (i.e., χ xz,zx MS ¼ 0 and π xz,zx MS ¼ 0), then R TE TM ¼ 0 and T TE TM ¼ 0, and R TM and T TM reduce to Eqs. (16) and (17) given in Ref. 28.…”

“…Over the years, frequency selective surfaces (FSS), and more recently metasurfaces, have been used to achieve polarization conversion. [9][10][11][12][13][14][15][16][17][18][19][20] Most of the metasurface work has been limited to metafilm-type structures. In this paper, we discuss how metascreen-type structures can be used to perform polarization conversion and show how the various surface parameters give rise to these effects.…”

Ultra-thin optical vortex phase plate based on the L-shaped nanoantenna for both linear and circular polarized incidences

“…Due to the 45°-directed symmetric axis (special geometric symmetry) of the L-shaped antenna, the induced scattered field have the same amplitudes and phases accordingly [35] for the incidences of XLP, YLP and CP lights. And, the corresponding scattered fields can be expressed as [36]: …”

Dielectric Metasurface-Based High-Efficiency Mid-Infrared Optical Filter

“…With the development of nanofabrication techniques, a new kind of material (i.e., metasurfaces) is a promising solution, with significant properties of artificially engineered optical response and high integration [ 5 , 6 , 7 ]. The first proposed metasurface is composed of subwavelength plasmonic nanoantennas, arranged in two-dimensional arrays; therefore, both the amplitude and phase of the incident beam could be artificially controlled through the local resonance of each of the nanoantennas [ 8 , 9 , 10 ]. However, the intrinsic loss of plasmonic structure in the optical range still hinders the use of metasurfaces as practical filters, even though tremendous efforts for enhancing the efficiency have been made [ 11 , 12 , 13 ].…”