Generation and characterization of polarization-shaped femtosecond laser pulses

We demonstrate the generation and complete characterization of femtosecond laser pulses which change their intensity, frequency, and light polarization almost arbitrarily within a single pulse employing the new technique of femtosecond polarization pulse shaping. Specifically, the degree of polarization ellipticity as well as the orientation of the elliptical principal axes can be varied as a function of time in a completely controllable manner, using a 128-pixel, two-layer, liquid-crystal display (LCD) inside a zero-dispersion compressor. A mathematical formalism is presented with which polarization-shaped pulse parameters can be calculated and used to generate intuitive quasi-three-dimensional electric field representations. However, laboratory realization requires accurate and complete experimental pulse characterization methods. For this purpose, the technique of dual-channel spectral interferometry is employed. Furthermore, Jones calculus for polarization- shaped pulses with experimentally determined Jones matrices is developed. It can be used to predict and account for all pulse-shape modifications occurring in various optical elements of the pulse shaper and the experimental setup.