title: Magnetic-Polaron-Induced Enhancement of Surface Raman Scattering.
abstract: The studies of the effects of magnetic field on surface enhanced Raman scattering (SERS) have been so far limited to the case of ferromagnetic/noble-metal, core/shell nano-particles, where the influence was always found to be negative. In this work, we investigate the influence of magnetic field on a diluted magnetic semiconductor/metal SERS system. Guided by three dimensional finite-difference time-domain simulations, a high efficient SERS substrate was obtained by diluting Mn into Au-capped ZnO, which results in an increase of the dielectric constant and, therefore, an enhancement of Raman signals. More remarkably, an increase of intensities as well as a reduction of the relative standard deviation (RSD) of Raman signals have been observed as a function of the external magnetic strength. We ascribe these positive influences to magnetic-field induced nucleation of bound magnetic polarons in the Mn doped ZnO. The combination of diluted magnetic semiconductors and SERS may open a new avenue for future magneto-optical applications.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong SAR, China.|Shenzhen Research Institute, City University of Hong Kong, High-Tech Zone, Nanshan District, Shenzhen 518057, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Shao
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials Laboratory (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Liao
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong SAR, China.|Shenzhen Research Institute, City University of Hong Kong, High-Tech Zone, Nanshan District, Shenzhen 518057, China.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ruotolo