Nonlinear optical absorption in silver nanosol

Nonlinear optical properties of triangular silver nanomaterials

Size-controlled synthesis of metal nanostructures has opened many new possibilities to design ideal building blocks for future nanodevices. By solution-based method, silver triangular nanoprisms of different sizes (edge length) have been synthesized. First hyper-polarizabilities of silver triangular nanomaterials were measured using hyper-Rayleigh scattering technique. We have shown that both l...

Nonlinear photoacoustics for measuring the nonlinear optical absorption coefficient.

We report a novel photoacoustic Z-scan (PAZ-scan) technique that combines the advantages offered by the conventional Z-scan method and the sensitivity of the photoacoustic detection. The sample is scanned through the focused laser beam and the generated photoacoustic signal is recorded using a 10 MHz focused ultrasound transducer. Since the signal strength is directly proportional to the optica...

Optical absorption resonances of dye-coated silver-island films.

We have used Mie theory to account for the features of the transmission spectra of dye-coated silver-island films. The unusual behavior of the spectra arises from the effect of the dispersion and damping of the optical response of the absorbing coating on the structural resonances of the silver islands. Our modeling indicates that the power dissipation in the dye coating is enhanced compared wi...

Nonlinear optical absorption and dynamics in quantum wells

We present measurements of differential transmission and four-wave mixing in GaAs quantum well structures at 1.8 K near the inhomogeneously broadened lowest heavy-hole (hhl) exciton resonance using narrow band cw excitation. The data show an increase in absorption and an excitation lifetime of order l-10 ps outside the spectral hole produced by the pump. The long lifetime and the experimentally...

Two photon absorption, nonlinear refraction, and optical limiting in semiconductors