Open AccessAbnormal spectral bands in broadband sum frequency generation induced by bulk absorption and refraction
Author(s) -
Yuhan He,
Yongyan Zhang,
He Ren,
Jingjing Wang,
Weig Guo,
ShiGang Sun,
Zhaohui Wang
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.028564
Subject(s) - optics , materials science , sum frequency generation , absorption (acoustics) , spectroscopy , refraction , spectral line , absorption spectroscopy , attenuation coefficient , refractive index , molecular physics , physics , nonlinear optics , laser , quantum mechanics , astronomy
In this paper, the time-resolved broadband sum frequency generation (BB-SFG) spectra from a bare Au surface with a distorted infrared (introduced with a 10 µm polyethylene film in the IR light path) and principal component generalized projection (PCGP) algorithm were used to investigate the bulk distortion on the measured BB-SFG spectra. Besides the SFG intensity reduction from the bulk absorption, the frequency dependent refraction of the bulk layer led to misleading SFG features at the positive delay times beyond the Au dephasing time. These results suggest that SFG spectroscopy is not entirely 'bulk-free' for the buried interfaces because of the bulk absorption and refraction of the incident pulses.