Second-harmonic microscopy of single micrometer-size particles on a substrate

Abstract

We report experimental observations of second-harmonic generation ͑SHG͒ from single micrometer-size polystyrene, silica, and polymethylmethacrylate spheres on flat substrates by SHG microscopy. At low input light intensities the SH signals depend quadratically on the intensity of the excitation beam, but at larger input intensities some of the SH signals increase exponentially with increasing input intensity. This exponential enhancement depends on particle size and sphere composition. We describe the experiments, and parametrize the observations.

Theory of optical second-harmonic generation from a sphere of centrosymmetric material: small-particle limit

“…Subsequent experiments exploited the surface sensitivity of SHG to monitor molecular adsorption on 22,23,29 and transfer between 30 particles, to observe molecular transport across the bilayer in liposomes, 21,31,32 to measure electric surface charge and potential, 33,34 and to observe the formation of a surface charge-transfer complex. 35 Other related experiments include SHG or sum-frequency generation from nanoparticles in solutions, [36][37][38][39][40][41][42][43][44][45][46][47][48][49] from embedded [50][51][52][53][54][55][56][57][58][59][60] and supported [61][62][63][64][65][66][67][68][69][70][71][72][73]…”

Dynamics of Micropollutant Adsorption to Polystyrene Surfaces Probed by Angle-Resolved Second Harmonic Scattering

“…Several theoretical formalisms have been developed to extract this orientation information, exploiting Mie scattering theory or Rayleigh-Gans-Debye (RGB) scattering theories 19 . Orientation information is particularly valuable for experiments in the vibrational region, wherein vibrational transitions can extract a detailed picture of the chemical structure of an interface 18,37,48,49 .…”

“…In addition to characterizing the adsorption thermodynamics of the subject molecule, the molecular orientation can also be determined if the full angle-resolved scattering pattern is recorded with polarization control of the input and output light. ,,,− Several theoretical formalisms have been developed to extract this orientation information, exploiting Mie scattering theory or Rayleigh–Gans–Debye scattering theories . Orientation information is particularly valuable for experiments in the vibrational region, wherein vibrational transitions can extract a detailed picture of the chemical structure of an interface. ,,, …”

Non-linear optical effects in SiCxN1−xO large-sized nanoclusters

“…Investigation of semiconductor nanocrystals is recently causing considerable experimental and theoretical interests [1][2][3][4][5][6]. There are many investigations devoted to changes of the band structure due to confinement-inducing (induced) quantisation of the continuous band states [7,8].…”