Enhanced Second Harmonic Generation by Mode Matching in Gain-assisted Double-plasmonic Resonance Nanostructure

Abstract

We theoretically study the gain-assisted double plasmonic resonances to enhance second harmonic generation (SHG) in a centrosymmetric multilayered silver-dielectric-gold-dielectric (SDGD) nanostructure. Introducing gain media into the dielectric layers can not only compensate the dissipation and lead to giant amplification of surface plasmons (SPs), but also excite local quadrupolar plasmon which can boost SHG by mode matching. Specifically, as the quadrupolar mode dominates SHG in our nanostructure, under the mode matching condition, the intensity of second harmonic near-field can be enhanced by 4.43 × 102 and 1.21 × 105 times when the super-resonance is matched only at the second harmonic (SH) frequency or fundamental frequency, respectively. Moreover, the intensity of SHG near-field is enhanced by as high as 6.55 × 107 times when the nanostructure is tuned to double super-resonances at both fundamental and SH frequencies. The findings in this work have potential applications in the design of nanosensors and nanolasers.

High-purity foam-like micron-sized gold cage material with tunable plasmon properties

“…Further, this was accompanied by a red shift of the bands. Pan et al 31 theoretically calculated the gain-assisted double plasmonic resonances to enhance second harmonic generation (SHG) in centrosymmetric multilayered nanocomposites. Moreover, PS@ Au synthesized in this study showed ultra-wideband absorption due to coupling between two different layers of the nanogold shell.…”

Spaser and Optical Amplification Conditions in Graphene-Coated Active Wires

“…Replacing into eqaution (10) the expression of ε 1 given by equation (15), after expanding in powers of y = ε di ε ∞ +ε2 , we obtain,…”

“…Since its proposal in 2003 1 and its first experimental demonstrations in 2009, 2 a wide variety of geometries and materials/metamaterials for the cavities as well as different compounds for the optical-gain medium have been considered. [3][4][5][6][7][8][9][10][11][12][13] Since the first experimental demonstrations in 2009, a wide variety of geometries and materials/metamaterials for the cavities as well as different compounds for the optical-gain medium have been considered 1,[3][4][5][6][7][8] .…”

Spaser and optical amplification conditions in graphene-coated active wires

“…Due to the coupling of localized surface plasmons (LSPs) with electromagnetic radiation, a spaser can confine light at subwavelength scales, which can be used to provide a controllable source of on-demand high-intensity electromagnetic fields beyond the diffraction limit. Since its proposal in 2003 [1] and its first, to the best of our knowledge, experimental demonstrations in 2009 [2], a wide variety of geometries and materials/metamaterials for the cavities as well as different compounds for the optical-gain medium have been considered [3][4][5][6][7][8][9][10][11][12][13]. Despite the development of many advanced spasers, most of the research in this area has been focused on natural plasmonic materials such as metals, which have a number of shortcomings, most notably power losses and a fixed charge density that finds applications in the visible and near-infrared range, but not in the mid-infrared and terahertz (THz) region.…”