A nanoscale gap aperture has been used as a fundamental tool for diverse applications. In this paper, we investigate the effect of nanogap aperture parameters on optical sensors, primarily based on surface plasmon resonance. A simple 2-D model was used for DNA immobilization and hybridization, in which nanogap enables light-matter colocalization to amplify detection signatures, thereby enhancing performance characteristics. Interestingly, the optimum gap geometry that produces maximum light-matter overlap and the largest resonance shift was not associated with the smallest gap size. Highest sensitivity was observed to correlate with negative resonance shift due to increased damping as well as the excitation of higher order surface plasmon polariton modes. Zero-shift nanogap was also discussed. The results suggest that careful design of nanogap apertures should be carried out to make the most of what they can achieve.
Bibliographical noteFunding Information:
Manuscript received June 28, 2017; revised August 6, 2017; accepted September 6, 2017. Date of publication September 10, 2017; date of current version October 12, 2017. This work was supported by the National Research Foundation (NRF) funded by the Korean Government under Grants NRF-2012R1A4A1029061 and 2015R1A2A1A10052826. The work of E. Sim was supported by the NRF under Grant NRF-2017R1A2B2003552. (Corresponding author: Donghyun Kim.) C. Lee and D. Kim are with the School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea (e-mail: email@example.com; firstname.lastname@example.org).
This work was supported by the National Research Foundation (NRF) funded by the Korean Government under Grants NRF- 2012R1A4A1029061 and 2015R1A2A1A10052826. The work of E. Sim was supported by the NRF under Grant NRF-2017R1A2B2003552.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics