The spectrum of the temporal traces obtained from a phase-sensitive optical time-domain reflectometer is theoretically and experimentally analysed, demonstrating its dependence on the incident optical pulse shape. Numerical simulations and theoretical results are validated experimentally, showing a good matching for rectangular optical pulses. The influence of the photodetector bandwidth on the...

We report the experimental demonstration of all-optical format conversion by exploiting the cascaded second-harmonic generation and difference-frequency generation (cSHG/DFG) in a periodically poled lithium niobate (PPLN) waveguide assisted by the reflective semiconductor optical amplifier (RSOA)-based active mode-locking. 10 and 20 Gbit/s format conversions from non-return-to-zero (NRZ) to ret...

A nonlinear optical processor that is capable of true real-time conversion of spatial-domain images to ultrafast time-domain optical waveforms is presented. The method is based on four-wave mixing between the optical waves of spectrally decomposed ultrashort pulses and spatially Fourier-transformed quasi-monochromatic images. To achieve efficient wave mixing at a femtosecond rate we utilize a c...

We experimentally study a new regime for supercontinuum (SC) generation in the nanosecond pulsed regime using a microstructured optical fiber with two zero-dispersion wavelengths (ZDWs). Pumping at 1535 nm around the second ZDW yields a nearly flat SC over 1350–1700 nm. The interplay between the effects of modulation instability and stimulated Raman scattering are described through simple phase...

A novel source of continuous-wave terahertz radiation based on difference frequency generation (DFG) in GaAs crystal is proposed. Phase matching is provided using integration of appropriate optical and terahertz waveguides based on dispersive properties of GaAs. The output frequency can be tuned between 0-3.5 THz by tuning the incident wavelengths in the range of 1.5-1.6 microm.

We show that the pump–to–signal power conversion efficiency of parametric chirped-pulse amplifiers made with periodically poled materials operating with multicolor spatial solitons can be significantly enhanced by employing engineered quasi-phase-matching gratings. Applications include compact sources of high-energy ultrashort pulses in diffraction-limited high-quality beams. © 2002 Optical Soc...

We demonstrated conversion of optical signals from 1550nm band to the 1300nm band in silicon waveguides. The conversion is based on parametric Stokes to anti-Stokes coupling using the Raman susceptibility of silicon. Achieving high conversion efficiency requires phase matching in the waveguides as well as means to reduce waveguide losses including the free carrier loss due to two photon absorpt...

We show theoretically that a chirped quasi-phase-matching nonlinear crystal structure can significantly enhance the axial resolution in quantum optical coherence tomography by increasing the spectral width of the generated entangled photon pairs. For pulsed pumps we show how the pump-pulse duration affects the maximum resolution attainable.

It is theoretically demonstrated that Rabi interband oscillations are possible in waveguide arrays. Such transitions can take place in optical lattices when the unit-cell is periodically modulated along the propagation direction. Under phase-matching conditions, direct power transfer between two Floquet-Bloch modes can occur. In the nonlinear domain, periodic oscillations between two different ...