Donald J Dr Harter

Generation of dual-wavelength pulses by SHG with QPM gratings

We demonstrate generation of two synchronized picosecond pulses at different wavelengths around 778 nm by SHG of a femtosecond pulse. We use nonlinear frequency filtering with QPM gratings which allowed us to obtain the second-harmonic spectral intensities that are higher than the spectral intensities of the pump.

Quasi-phase-matching for ultrafast nonlinear optics

Summary form only given. Quasi-phase-matching (QPM) has developed rapidly over the past several years as an important tool for efficient nonlinear optical frequency conversion. This talk reviews basic ultrafast QPM frequency conversion experiments, such as second-harmonic generation of fs mode locked erbium-doped fiber lasers with efficiencies of 90%/nJ, optical parametric generation (OPG) with a threshold 50 nJ, and synchpumped optical parametric oscillators (OPOs) with 30-mW threshold power, order of magnitude improvements over conventional materials.

Engineerable femtosecond pulse shaping using SHG with aperiodic QPM structures

Manipulation of the temporal shape of ultrashort optical pulses is important for many applications. Conventional pulse-shaping techniques filter optical frequency components spatially dispersed with a grating apparatus. Here we demonstrate an alternative approach, which uses second-harmonic generation (SHG) with aperiodic quasi-phase-matching (QPM) structures. This technique allows generation of almost arbitrary second-harmonic waveforms using compact monolithic devices.

Time-Domain Jitter Measurement of Modelocked Fiber Lasers

The timing jitter of modelocked Er:doped fiber lasers is measured using a new time-domain method involving cross-correlation. The measured jitter is compared with the quantum-limited timing jitter predicted by the theory of Haus & Mecozzi.