Phase matching for surface plasmon enhanced second harmonic generation in a gold grating slab

Abstract

Surface plasmon enhanced second harmonic generation in gold grating slabs was investigated. The efficiency is analyzed with respect to the phase matching at the fundamental and the second harmonic frequencies. A classical electromagnetic model was developed under the weak nonlinearity approximation and solved by the finite element method. The measured zeroth order transmitted second harmonic intensity was found to be in quantitative agreement with numerical results. It is shown experimentally and numerically that proper phase matching at both frequencies improves the second harmonic efficiency.

Enhanced Second Harmonic Generation from Ferroelectric HfO2-Based Hybrid Metasurfaces

“…For the Au structure, only the surface χ (2) coefficient (χ zzz (2) (Au)) is contributing to the SHG . Here, a classical model combined with Maxwell’s equation is used to simulate the SHG of gold. , The nonlinear polarization of the Y:HfO 2 film is computed by assuming an effective χ eff (2) coefficient (see Supplementary Note 1). SHG from TiN is ignored due to its much smaller χ (2) coefficient compared to Au as well as the much lower electric field intensity in TiN, as shown in Figure c.…”

Surface plasma wave assisted second harmonic generation of laser over a metal film

“…37 The present study provides an alternative scheme to SPW assisted second harmonic generation using nanoparticles. 35 Fabrication of density ripple with required wave number over a metallic film is much easier than employing nanoparticles. Further, the emission of second harmonic radiation over a larger area is another advantage which increases harmonic power content.…”

“…The phase mismatch can be significantly controlled if the required additional momentum can be provided by employing a grating structure or a density ripple. 35,36 In this paper, we investigate SPW assisted second harmonic generation from a metal film, comprising of a density ripple at the rear end to provide the additional momentum for phase matching. The SPW excited bt laser over metal-free space boundary exerts a second harmonic ponderomotive force on metal electrons.…”

Nonlinear optics on nano/micro-hierarchical structures on metals: focus on symmetric and plasmonic effects

“…Despite the extensive research on the SP-assisted nonlinear processes in pure metals, hybrid, or composite materials [22,29–33], a systematic study on the effects of micro/nano-hierarchical structures on nonlinear optical processes is currently lacking. As mentioned above, both nanostructures and microstructures are important for generating SPs.…”