Dispersion Managed Solitions

We helped pioneer the understanding of a pulse format called Dispersion Managed Solitons. As shown below one of our loops is 107 km long. As shown below an optical pulse which is temporally dispersed propagates in 100 km of optical fiber. In this example, the pulse compresses due to the dispersion of the fiber until it reaches the middle of the fiber and then as it spreads temporally in the second half of the fiber. In the next 7 km piece of fiber the pulse repeats the process but the next dispersion is slightly positive. Normally this would cause the pulse to spread after repeated circulations in the loop. However, the nonlinear interaction of the optical pulse and the atoms in the fiber just balances this spreading and the pulse returns to its original shape at the beginning of the 100 km fiber. In this way the pulse repeats this each circulation in the loop. This effect allows yields a larger signal to noise ratio and hence longer distances of propagation at a given bit-error ratio.