Coherent transients in active optical fibers.

Optical coherent transients have been generated in Nd(3+) doped silica glass fibers. Two and three pulse photon echoes were used between 0.05 and 1K to study optical dephasing mechanisms of ions in a disordered environment. The results are explained by a model which incorporates elastic dipolar interactions between the ions and atomic tunneling systems in the glass. Various issues associated with applying optical coherent transients to active fibers are discussed.