Trapping mid-infrared rays in a lossy film with the Berreman mode, epsilon near zero mode, and magnetic polaritons

Abstract

Triple mechanisms were employed to trap mid-infrared (mid-IR) rays within a semi-transparent SiO(2) film sandwiched between gold gratings and a gold substrate. Dimensions of four absorbers were explicitly determined using an LC (inductor-capacitor) circuit model considering the role transition of SiO(2) film. The film behaves as a capacitance and an inductance when the real part of relative electric permittivity for SiO(2) is positive and negative, respectively. At the normal incidence of transverse magnetic waves, every absorptance spectrum of absorbers showed a peak at wavelength λ = 10 μm due to the first mode excitation of magnetic polaritons (MP). At oblique incidence, the Berreman mode led to another peak at λ = 8 μm while its bandwidth was expanded with epsilon near zero mode excited by diffracted waves. The full-width-at-half-maximum of both peaks exceeded 0.6 μm thanks to the SiO(2) loss. Other minor absorptance peaks in the mid-IR were caused by variants of the same MP mode.

Absorption Properties of Simply Fabricated All-Metal Mushroom Plasmonic Metamaterials Incorporating Tube-Shaped Posts for Multi-Color Uncooled Infrared Image Sensor Applications

“…In the present study, we prepared devices operating primarily in the vicinity of 10 µm, corresponding to the region applicable to the detection of gases and living beings and where MIM structures have difficulty operating [22]. In these devices, the p, t m , h, and t b parameters were fixed at 6.0 µm, 100 nm, 200 nm, and 100 nm, respectively.…”

“…Photonics 2016, 3, 9 2 of 8 [9], which prevents these absorbers from operating at long IR wavelengths in the vicinity of 10 μm [22]. This is an important wavelength region for the observation of living beings as well as for the sensing of gaseous compounds such as ethanol.…”

“…Metal-insulator-metal (MIM)-type absorbers [20,21] are important candidates for wavelength-selective uncooled IR sensors due to their small thermal mass and size. However, the presence of insulating layers, including SiO 2 , Al 2 O 3 , and SiN, can cause spurious peaks due to intrinsic absorption [9], which Photonics 2016, 3, 9 2 of 8 prevents these absorbers from operating at long IR wavelengths in the vicinity of 10 µm [22]. This is an important wavelength region for the observation of living beings as well as for the sensing of gaseous compounds such as ethanol.…”

Fano resonance in asymmetric-period two-dimensional plasmonic absorbers for dual-band uncooled infrared sensors

“…Dual-band operation is particularly important with regard to analytical sensing applications, such as gas and material sensing as one potential use. Metal-insulator-metal absorbers 18,19 are good candidates for this type of dual-band operation; 20,21 however, such structures have restrictions in terms of the operation wavelength range 22 and require precise control over the metal patch size 23 for control of the absorption wavelength, which leads to complex manufacturing procedures and thus increases cost. On the other hand, two-dimensional plasmonic absorbers (2-D PLAs) have rich potential for a variety of practical applications due to their wide operational range in the middle-and long-wavelength IR regions, in addition to their simple fabrication processes and structural robustness.…”

Theoretical investigation of all-metal-based mushroom plasmonic metamaterial absorbers at infrared wavelengths

“…Metal-insulator-metal structures [18][19][20][21] based on plasmonic metamaterials are important candidates for high-performance absorbers, which control the absorption wavelength according to the surface resonator size beyond the surface array period. However, insulator layers such as SiO 2 and SiN cause an additional absorption peak, restrict the operation wavelength to near the MWIR region due to their intrinsic absorption, 22 and also increase the thermal mass. Therefore, we have proposed three-dimensional (3-D) or mushroom plasmonic metamaterial absorbers (MPMAs), 23 as well as a suitable fabrication method.…”