Bideposited silver nanocolloid arrays with strong plasmon-induced birefringence for SERS application

Abstract

Silver nano-rod, nano-zigzag, nano-saw, and nano-particle arrays are fabricated with glancing angle bideposition. The structure-dependent anisotropic optical properties of those bideposited nanostructured arrays are measured and investigated. The equivalent birefringence values of nano-rod and nano-zigzag arrays are much larger than crystals found in nature and liquid crystal used in display products. The fact that induced localized plasmon-magnetic field between nanorods dominates the strong phase retardation between p-polarized and s-polarized transmitted wave. For the nano-saw, the strong localized electric field induced between the saw teeth leads to strong SERS signals. Although the bideposited nanoparticles own weak morphological anisotropy, strong optical phase retardation is still detected at wavelengths near 400 nm.

Smart design of high‐performance surface‐enhanced Raman scattering substrates

“… 42 The 2D hexagonal close‐packed superlattices of Ag nanoparticles formed in these films allow for SERS detection over a large area with excellent uniformity and high EFs. Ag array assembled by Ag nanoparticles or nanowire also present excellent SERS activity 43–45 . Using graphene to isolate nanowire arrays can not only effectively control the distance between nanowires, but also enhance the stability of the materials.…”

Recent advances in non‐plasmonic surface‐enhanced Raman spectroscopy nanostructures for biomedical applications

“…23 Recently, laser-driven birefringence has been reported for SERS. 24,25 As described in these works, birefringence generated under laser irradiation in nanofibers could induce multiple Raman scattering, resulting in plasmon-free SERS activity. The fundamental aspects for SERS effect based on birefringence is still unclear.…”

“…This phenomenon has also been reported on non‐plasmonic substrates, such as nanostructured carbon surfaces (Sil et al, 2013). Recently, laser‐driven birefringence has been reported for SERS (Jen et al, 2020; Qiu et al, 2015). As described in these works, birefringence generated under laser irradiation in nanofibers could induce multiple Raman scattering, resulting in plasmon‐free SERS activity.…”

Polarized SERS substrates with directionality, repeatability and orderability: an anisotropic Ag nanocavity array

“…The highest enhancement factor measured by our Ag nanocavity structure is 8.1 × 10 5 , which shows the significant SERS enhancement effect. 49,50…”