Near-field spectral shift of a zero-order Bessel beam scattered from a spherical particle

Abstract

Within the accuracy of the first-order Born approximation, expressions are derived for the near-zone spectrum of a zero-order Bessel beam scattered from a spherical particle whose correlation function satisfies a Gaussian distribution. The dependence of the spectral shift and spectral switch of the scattered field on the effective size of the scattering potential (ESSP) are determined by numerical simulations. It is shown that the spectral shift of the scattered field does not occur along the longitudinal propagation direction. Furthermore, when the medium’s ESSP is comparable with the central wavelength of the beam, the spectrum of the scattered field loses the Gaussian distribution and exhibits a blue shift as the reference point sufficiently far away from central origin. These results may have prospective applications in guiding tiny particles when the near-zone spectrums of scattered beams are captured and analyzed.

Ag@ZIF-67 decorated cotton fabric as flexible, stable and sensitive SERS substrate for label-free detection of phenol-soluble modulin

“…Thus, the portability or exibility of SERS substrates matters. Also, exible SERS substrates, including paper-based (Yu & White, 2013), polyester (PET) lm-based (F. Chen, Li, Belafhal, Cha q, & Sun, 2018), tape-based (Liyanage et al, 2018), silicon chip-based (N. Chen et al, 2017) and swab-based (Gong et al, 2014), have been developed by demands of applications in recent years. Although these approaches may have improved the e ciency and reduced the cost of the fabrication of SERS substrates, more works are needed for the evaluation and development of applications with a wider range of target molecules.…”