Lee, Soo Hyun Roh, Yeeun Lee, Sang-Hun Ryu, Yong-Sang Ju, Byeong-Kwon Seo, Minah 2024-01-19T15:33:26Z 2024-01-19T15:33:26Z 2021-09-02 2021-01-04 1094-4087 https://pubs.kist.re.kr/handle/201004/117547 Signal enhancement of spectroscopies including terahertz time-domain spectroscopy (THz-TDS) and surface-enhanced Raman scattering (SERS) is a critical issue for effective molecular detection and identification. In this study, the sensing performance between THzTDS and SERS individually accompanied by the proper plasmonic subwavelength structures was compared. For the precisely quantitative study on the optical properties of rhodamine 6G (R6G) dyes, SERS incorporates with the non-linearly enhanced Raman emissions at the molecular characteristic peaks while THz-TDS refers to the transmittance change and the shift of the spectral resonance. The local molecular density-dependent trade-off relationship between limit-of-detection and quenching was observed from both measurements. The specificity for two samples, R6G and methylene blue, is determined by the discriminations in spectral features such as the intensity ratio of assigned peaks in SERS and transmittance difference in THz-TDS. The comprehension of field enhancement by the specific nanostructures was supported by the finite-element method-based numerical computations. As a result, both spectroscopic techniques with the well-tailored nanostructures show great potential for highly sensitive, reproducible, label-free, and cost-effective diagnosis tools in the biomedical fields. (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement English OPTICAL SOC AMER FIELD ENHANCEMENT NANOPARTICLES SPECTROSCOPY TRANSFORMATION ARRAYS Direct comparison with terahertz metamaterials and surface- enhanced Raman scattering in a molecular-specific sensing performance Article 10.1364/OE.412474 1 OPTICS EXPRESS, v.29, no.1, pp.12 - 23 OPTICS EXPRESS 29 1 12 23 scie scopus 000605304600002 2-s2.0-85099075847 Optics Optics Article FIELD ENHANCEMENT NANOPARTICLES SPECTROSCOPY TRANSFORMATION ARRAYS