Re: Optical dispersion in fibers

[brian whatcott <inet@INTELLISYS.NET>]

At 09:42 1/29/00 -0500, Ludwik wrote:
...
> And, as John wrote,
> > Solving the spatial problem doesn't get rid of dispersion
> > (which occurs in frequency-space, even in a fiber with
> > a single spatial mode).
>
> The optical amplification, however, should be useful in
> overcoming limits imposed by dispersion.

I should know better than to offer off the cuff thoughts on a
current research topic. I am even more likely to contribute to the
delinquency of minors when I offer knee-jerk responses at 3:30
 in the morning.

 In particular, in line optical amplification does not normally help
with dispersion issues (as I enthused) even where skinny
monomode fibers are operated near nominally zero dispersion
regions. Fortunately, there is a wealth of relatively recent
research material available on the web as a corrective.

   Perhaps I should content myself (among the hand-wringing of
web-authors on the difficulties of attempting fiber predictions
of pulse behavior using the non-linear Schrodinger equation)
with the results of an earlier generation of proponents of
 bulk transport by soliton methods: I refer to the folks who
 were not pleased to be called 'bargees' (prefering the title,
'narrowboat-men')  who found that a threshold intensity
 of wave front on an inland canal was necessary to propagate
such a low-loss wave:
they used two shire horses in tandem for the wave launching of
 the transport packet ..er.. barge, before continuing mile on
 mile with a single hauler.  They found that intensity non
linearities are of interest (rather than spatial non-linearities).

Here is an URL among the overwhelming numbers from SPIE, etc:

<http://www.ece.wpi.edu/courses/ee535/hwk96/hwk5cd96/li/li.html#intro>


My eye was also caught by this abstract from Yuk, Yu, Chui, and Shum.

Tony I. Yuk, Univ. of Hong Kong, Hong Kong, Hong Kong et al:

   Abstract: This paper describes the development of numerical
          simulation models of soliton systems using a newly
          developed Fourier Series Analysis Technique to analyze
          the nonlinear Schrodinger equation of soliton
          propagation. Generation of sub-picosecond solitons in
          an active mode-locked fiber ring laser with amplitude
          and phase modulators and soliton pulse compression
          mechanisms using dispersion decreasing fiber are
          investigated.

Sincerely
Brian


brian whatcott <inet@intellisys.net>
Altus OK