Journal: ACS Applied Materials & Interfaces

Article Title: Strong Chiro-Optical Activity of Plasmonic Metasurfaces with Inverted Pyramid Arrays

doi: 10.1021/acsami.4c19803

Figure Lengend Snippet: SEM images and optical properties of plasmonic chiral metasurfaces. (A, B) SEM images of gold-coated patterned SU8 on top of a glass substrate. Lattice parameter of 600 nm and pyramid size of 461 ± 12 nm. Scale bars in panels (A, B) are 5 and 2 μm, respectively. (C) Experimental and (D) calculated transmittance spectra. Left circular polarized (LCP) and right circular polarized (RCP) incident light spectra are shown by blue and red lines, respectively. (E, F) experimental and calculated differential transmittance (Δ T = T LCP – T RCP ) extracted from panels (C, D). Vertical dashed lines at (C–F): λ INT = 521 nm, λ MAX = 705 nm, and λ RA = 930 nm. FDTD calculated electric field distribution cross section ( xz ) at λ MAX , for (G) LCP and (H) RCP. FDTD model structure parameters LP: 600 nm, pyramid size: 450 nm, mismatch angle: 24°, Au thickness: 40 nm, substrate n = 1.53, λ = 710 nm. Scale bars in panels (G, H) are 200 nm.

Article Snippet: To validate our experimental results, we performed numerical simulations using the finite-difference time-domain (FDTD) method (Ansys FDTD-Solutions, Lumerical).

Techniques:

Journal: ACS Applied Materials & Interfaces

Article Title: Strong Chiro-Optical Activity of Plasmonic Metasurfaces with Inverted Pyramid Arrays

doi: 10.1021/acsami.4c19803

Figure Lengend Snippet: (A) Calculated transmittance spectra at normal incidence of plasmonic chiral metasurfaces. Left circular polarized (LCP) (dashed lines) and right circular polarized (RCP) (solid lines), the color of the lines corresponds to the mismatch angle θ m = 0° (black), 5° (red), 10° (green), 15° (blue), 20° (cyan). FDTD parameters LP: 600 nm, pyramid size: 450 nm, θ m : 22°, Au thickness: 50 nm, substrate n = 1.53. (B) calculated g-factor dependence on mismatch angle (shaded blue curve with colored dots) (for d = 450 (green), 475 (yellow), 500 (black), 510 (gray), and 525 nm (blue)) and experimental g-factor values obtained in samples with different θ m (red dots). (C) Enantiomorph behavior: g-factor spectra for θ m = +24° (red line) and θ m = −23° (blue line). Inset: SEM images of each Au-coated sample.

Article Snippet: To validate our experimental results, we performed numerical simulations using the finite-difference time-domain (FDTD) method (Ansys FDTD-Solutions, Lumerical).

Techniques: