Open AccessUltra-fast luminescence of nano-gold film structure
Author(s) -
Fang Shen,
Guyu Zhou
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1676/1/012104
Subject(s) - photoluminescence , materials science , luminescence , colloidal gold , femtosecond , surface plasmon resonance , optoelectronics , plasmon , laser , photoluminescence excitation , resonance (particle physics) , nanoparticle , nanotechnology , optics , atomic physics , physics
The Fermi level of gold is not in the band gap, but in the sp band. Therefore, macroscopic gold is usually a non-luminescent material. Unlike gold bulk materials, frequency down-conversion photoluminescence and enhanced photoluminescence from gold nanoparticles have been studied, and the intensity of their photoluminescence is affected by the size, shape and plasmon resonance of the gold nanoparticles. In particular, plasmon resonance helps to increase the photoluminescence intensity by several times than the intensity in the macroscopic gold structure. Gold nanoparticles can also produce photoluminescence including second harmonic and third harmonic under intense photo excitation. Here, in order to study the luminescence properties of gold nanostructures under femtosecond laser, we applied a 5 nm gold film on a Si3N4 substrate by magnetron sputtering. The nano-gold film was excited using a femtosecond laser with an incident peak power density of 2.3 × 10 9 W/cm 2 and 4.5 × 10 9 W/cm 2 . We explained that by studying the excitation spectra of nano-gold structures, we can see that SHG occurs at high power density and frequency shift occurs.