3:15 PM - 3:30 PM
▼ [18p-A305-9] Control of dual-resonant infrared metasurfaces for Surface enhanced infrared absorptions
Keywords:surface-enhanced infrared absorptions, dual-resonant
Surface plasmon resonances (SPRs) play an important role in real-time monitoring of intermolecular dynamics, which depend on the change of the surrounding refractive index. In contrast, surface-enhanced infrared absorptions (SEIRAs) can identify biomolecules of different chemical nature by matching the resonance peaks of the metasurfaces with the vibrational peaks of the molecules. The SEIRA technique is expected to have significant clinical potential for monitoring in-situ biological interactions. Most of the biomolecules, such as blood, saliva, and urine, exist in aqueous solution. However, water medium poses difficulties for real-time detection of biomolecular interactions because of the strong absorptions in the IR range. The SEIRA based on metal metasurfaces has more benefits for monitoring biological interactions due to the short penetration depths of metal surfaces. Furthermore, the molecular vibrations widely distribute in the IR range from 3,000 to 500 cm-1. The metasurfaces with a single resonance can only measure only a narrow wavelength range, which is disadvantages of using the resonance effect. We are required to develop a new method to simultaneously measure different molecular vibrations at once. In this presentation, we design IR metasurfaces with dual resonances based on gold for measuring bioreactions in aqueous solution.
Reflectance spectra of the following metasurfaces were obtained theoretically by 3D-FDTD analysis. In this work, we employed infrared metasurfaces consisting of large and small dots to obtain dual-resonant peaks in the IR range. From calculation results of 3D-FDTD analysis, we found that the metasurfaces with large and small dots had dual resonant peaks at around 2800 and 1600 cm-1 that corresponded to the methyl- and amide-related vibrational peaks, which are expected for in-situ and dynamic monitoring of biological interactions in the IR range.
Reflectance spectra of the following metasurfaces were obtained theoretically by 3D-FDTD analysis. In this work, we employed infrared metasurfaces consisting of large and small dots to obtain dual-resonant peaks in the IR range. From calculation results of 3D-FDTD analysis, we found that the metasurfaces with large and small dots had dual resonant peaks at around 2800 and 1600 cm-1 that corresponded to the methyl- and amide-related vibrational peaks, which are expected for in-situ and dynamic monitoring of biological interactions in the IR range.