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We present an experimental and theoretical study of sum-frequency generation of two infrared photons and one visible photon in a lithium iodate crystal. The sum-frequency light can be generated directly in a third-order process as well as in two subsequent ...
A continuously tunable optofluidic distributed feedback (DFB) dye laser was demonstrated on a monolithic replica molded poly(dimethylsiloxane) (PDMS) chip. The optical feedback was provided by a phase-shifted higher order Bragg grating embedded in the liqu ...
We use sum-frequency generation spectroscopy (SFG) in the infrared 2800–3000 cm−1 spectral range and UV–vis spectroscopy (transmission) in the 450–650 nm spectral range in order to characterize vibrational and electronic properties of various interfaces co ...
One of the main drawbacks of Fourier domain optical coherence tomography (FDOCT) is the limited measurement depth range. Phase shifting techniques allow reconstructing the complex sample signal resulting in a doubled depth range. In current complex FDOCT r ...
The conception and realisation of a prototype 355nm wind lidar return signal simulator capable of simulating the Rayleigh and the Mie return signals is described. The system is based on a commercial dual wavelength 1064nm/532nm diode pumped solid state las ...
Gold nanoparticles with a diameter of approximately 20 nm have been observed at the polarized water/2-octanone interface by the nonlinear optical technique of second harmonic generation. Electric field induced adsorption of the gold particles at this liqui ...
In 2-color optical Kerr effect measurements of water, addnl. signals can occur in the pulse overlap region if the energy difference between pump and probe pulses approaches the Raman resonance of the OH-stretch vibration. These features can be understood b ...
Fourier domain optical coherence tomography (FDOCT) is a high speed imaging technique with high axial resolution in the micro-meter-scale range combined with a high sensitivity allowing to probe 3D volumes of weakly back- scattering biological tissues in-v ...
Frequency stabilization is generally performed by using atomic or molecular absorption lines. However, it is sometimes necessary to lock a laser at a frequency located outside of any absorption peaks. In this case, an offset locking configuration is necess ...
An experimental method is presented for characterization of the combined intensity and frequency modulation produced when the injection current of a laser diode is modulated. The reported technique is based on the analysis of the harmonic signals produced ...