Abstract

We wish to use atomic group-velocity dispersion to compress energetic copper-vapor laser- pumped dye-laser pulses from 40 ns to approximately 300 ps. This talk focuses on numerical results that illustrate coherent atomic effects on the process. Traditionally, analysis has been based on linear dispersion theory (LDT). This model represents the atoms as a static susceptibility. This susceptibility gives rise to the differential group delay required for compression of frequency-swept pulses. However, LDT is inadequate in analyzing compression in a regime in which the coherent transition rate (Rabi frequency) is comparable to the laser detuning. Here population transfer becomes significant, thus invalidating the concept of a steady-state dipole. An adequate representation of the atomic system requires solution of the coupled Maxwell-Bloch equations. We have developed a code to model near-resonant coherent propagation through inhomogeneously broadened two-level atoms.

© 1991 Optical Society of America