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High harmonic generation is used to probe vibrational and electronic dynamics in small molecules. We impulsively excite vibrations in CF3C1 and observe oscillations in the harmonic emission. We electronically excite CF3I and observe changes in the yield.

We demonstrated that both oxyhemoglobin and deoxyhemoglobin has sequential two- photon absorption properties that can serve as endogenous contrasts in microvasculature imaging. They can also be differentiated through their different excited state dynamics.

We report theoretical and experimental results of nonlinear absorption and refraction in a series of colloidal CdSe quantum-dots. A two-level-model is used to describe the nonlinearities when quantum-dots are excited close to their first resonance.

We propose a technique to obtain sub-wavelength resolution in imaging with 100% contrast using incoherent light. We can obtain a resolution of λ/N using coincidence detection of N photons emitted from N excited atoms.

Optical pump-probe measurements have been performed on superlattices of self-organised InAs quantum dots embedded in GaAs. These structures exhibit subpicosecond photocarrier lifetimes when excited at 800 nm, which increase with the ex situ annealing temperature.

We present the design, fabrication and testing results of a nano-scale quantum dot photodetector composed of quantum dots that are positioned between a nano-gap in electrodes and optically excited with CW light.

Transient dynamics of photoexcited carriers in MEH-PPV, PCBM-C60 and their blend is investigated by THz-TDS using a 400 nm optical pump and terahertz probe. Free and bound carriers are revealed in the measurement of the complex conductivity.

Using UV-near-field optical spectroscopy and AlGaN layers that exhibit a strong, red- shifted emission band, we demonstrate the existence of different localization regions that can be excited selectively with excitation below the bandgap.

Experiments on transverse detection of transient fluorescence excited by oscillating interference pattern in Er-doped fiber in spectral range 1480-1600 nm are reported. This technique is used for evaluation of local amplitude of the recorded population grating.

An all-optical switching with an ultrafast response time of femtosecond order is demonstrated in a two-dimensional polystyrene photonic crystal excited by a 9.7 MW/cm2 pump laser. High switching efficiency of about 70 % is achieved.

To understand the effects of electron accepting bridges on the nonlinear absorption, we characterized both two-photon and excited-state absorption spectra of three cyanine dyes of increasing electron acceptor strength.

Resonantly excited optical antennas are studied with near-field optical microscopy. The locally enhanced fields associated with antenna resonances are imaged by using a sharp metallic tip acting as a local scattering center.

The effects of the screening of the quantum-confined Stark effect in an InGaN/GaN quantum well, in which the photoluminescence spectrum blue shifts with excited carrier density, on the surface plasmon coupling are identified and quantified.

This paper reports on the nonlinear absorption (reverse saturation of absorption and saturation of absorption) spectrum of Chlorophyll A solution obtained through the white light continuum Z-scan technique.

Self-assembled nanostructures in transparent materials irradiated by ultrashort light pulses reveal two-dimensional periodicity. The mechanism of the phenomenon based on interference of bulk plasma waves excited via two plasmon parametric decay is proposed.