Double Blind Ultrafast Pulse Characterization by Mixed Frequency Generation in a Gold Antenna

Abstract

Ultrafast pulse characterization requires the analysis of correlation functions generated by frequency mixing of optical pulses in a nonlinear medium. In this work, we use a gold optical nanoantenna to generate simultaneously Four Wave Mixing and Sum Frequency Generation across the tuning range of a Ti: Sapphire and Optical Parametric Oscillator (OPO) system. Since metal nanoparticles create remarkably strong nonlinear responses for their size without the need for phase matching, this allows us to simultaneously characterize the unknown OPO pulse and its pump pulse using a single spectrogram. The nonlinear mixing is efficient enough to retrieve pulses with energies in the picojoule range.

Evidence of Cascaded Third-Harmonic Generation in Noncentrosymmetric Gold Nanoantennas

“…Such mechanism, which is commonly observed in non-centrosymmetric bulk crystals, eventually adds up to the THG from pure χ (3) -related currents and, if properly optimized, allows boosting the THG efficiency in these media [44][45][46][47][48] and even in mesoscopic non-centrosymmetric systems. 49,50 The presence of cascaded effects in THG seeded by SFG in plasmonic nanoantennas has been neglected in the literature thus far because of the large difference often reported between the SHG and THG emission yields.…”

“…However, sizeable SFG has been recently reported for some specific plasmonic nanostructures 15 and the optimization of SFG through intrapulse phase engineering has been exploited to maximize SHG in plasmonic nanoantennas. 47 Here we tentatively consider a surface Fig. 3d), the main polarization axis of the cascaded THG emission from Antenna R is strongly tilted.…”

Two‐Tier Nanolaminate Plasmonic Crystals for Broadband Multiresonant Light Concentration with Spatial Mode Overlap

“…[4][5][6][7][8] Nevertheless, for many nonlinear nanophotonics applications, it is highly desirable to use multiresonant plasmonic devices that can simultaneously enhance multiphoton excitation/emission processes in several different wavelength bands at the same hotspot locations. [9][10][11][12][13][14][15][16][17][18][19] For constructing multiresonant plasmonic devices, a general approach is to assemble multiple building-block plasmonic resonators within a very close distance; and the optical coupling between spectrally matched non-orthogonal elementary modes of building blocks can result in multiple hybrid plasmonic modes of different resonance wavelengths that spatially overlap. [20][21][22] Based on the geometrical configuration of building-block resonators, multiresonant plasmonic devices can be classified into three types: 1) in-plane arrangement, [9,11,12,15,18,[23][24][25][26][27] 2) core-shell arrangement, [14,[28][29][30][31][32] and 3) out-of-plane arrangement.…”

“…[9][10][11][12][13][14][15][16][17][18][19] For constructing multiresonant plasmonic devices, a general approach is to assemble multiple building-block plasmonic resonators within a very close distance; and the optical coupling between spectrally matched non-orthogonal elementary modes of building blocks can result in multiple hybrid plasmonic modes of different resonance wavelengths that spatially overlap. [20][21][22] Based on the geometrical configuration of building-block resonators, multiresonant plasmonic devices can be classified into three types: 1) in-plane arrangement, [9,11,12,15,18,[23][24][25][26][27] 2) core-shell arrangement, [14,[28][29][30][31][32] and 3) out-of-plane arrangement. [33][34][35][36][37] Since it is straightforward to create plasmonic systems with accurate nanoscale control of planar geometries by top-down nanolithography, most previous studies have focused on developing in-plane multiresonant plasmonic devices.…”

“…[33][34][35][36][37] Since it is straightforward to create plasmonic systems with accurate nanoscale control of planar geometries by top-down nanolithography, most previous studies have focused on developing in-plane multiresonant plasmonic devices. [9,11,12,15,18,[23][24][25][26][27] Despite the simplicity in design and fabrication, in-plane multiresonant plasmonic devices face two severe limitations due to the planar layout of multiple building-block resonators. 1) The device footprint tends to be large, and accordingly, the surface density of multiresonant hotspots is typically low; 2) Since the nearest-neighbor coupling of elementary modes dominates between in-plane arranged building-block resonators, the planar multiresonant systems usually support a limited number (<4) of hybridized plasmonic modes with spatial overlaps.…”