ABSTRACT
Line-by-line pulse shaping is demonstrated on a 890 MHz repetition rate mode-locked titanium sapphire laser. The high resolution pulse shaper is based on a virtual imaged phased array (VIPA) with a free spectral range of 25 GHz. For our implementation, the mask repeats every VIPA free spectral range, which corresponds to every 28 comb lines. Individual frequency modes from the laser are also resolved using the same VIPA paired with a diffraction grating to achieve a resolution of 357 MHz. Several output waveforms are compared with simulation to understand differences with the ideal case.
Subject(s)
Lasers , Models, Theoretical , Refractometry/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Telecommunications/instrumentation , Computer Simulation , Computer-Aided Design , Equipment Design , Equipment Failure Analysis , Light , Scattering, RadiationABSTRACT
Pulse shaping theory is extended to include rapid waveform update for line-by-line pulse shaping. The fundamental tradeoff between response speed and waveform fidelity is illustrated by several examples.
Subject(s)
Models, Theoretical , Optics and Photonics , Signal Processing, Computer-Assisted , Computer SimulationABSTRACT
A theoretical description of the pulse dynamics in a modelocked laser including gain dynamics is developed. Relaxation oscillations and frequency pulling are predicted that influence the pulse parameters. Experimental observations of the response of a mode-locked Ti:sapphire laser to an abrupt change in the pump power confirm that the predicted behavior occurs. These results provide a framework for understanding the effects of noise on the spectrum of the laser.
