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Solitonen...


Vortrag im Proseminar "Einführung in die Photonik" bei Dr. Dietrich Schilder, Berlin den 26.6.2003



Bild von John Scott Russell Entdeckung des Soliton-Phänomens 1834 durch John Scott Russell

"I was observing the motion of a boat which was rapidly drawn along a narrow channel by a pair of horses, when the boat suddenly stopped - not so the mass of water in the channel which it had put in motion; it accumulated round the prow of the vessel in a state of violent agitation, then suddenly leaving it behind, rolled forward with great velocity, assuming the form of a large solitary elevation, a rounded, smooth and well-defined heap of water, which continued its course along the channel apparently without change of form or diminution of speed. I followed it on horseback, and overtook it still rolling on at a rate of some eight or nine miles an hour, preserving its original figure some thirty feet long and a foot to a foot and a half in height. Its height gradually diminished, and after a chase of one or two miles I lost it in the windings of the channel. Such, in the month of August 1834, was my first chance interview with that singular and beautiful phenomenon which I have called the Wave of Translation". (Russell, 1844)




Definition:
Solitonen sind Wellen, die formstabil (nicht-dispersiv) über theoretisch unbegrenzte Strecken durch ein nichtlineares Medium propagieren.




  P(t)=P0sech2(t/T0)-Impulsverlauf (erstellt mit Matlab):
sech²-Form eines Solitonwellenpakets
Abriss der technischen Entwicklung:

1973 theoretische Vorhersage der Existenz von Solitonen auf Lichtwellenleitern (LWL) durch Hasegawa von AT&T Bell Laboratories.

1980 erster experimenteller Nachweis (Mollenhauer)

1992 fehlerfreie 5 Gbit-Übertragung über 15.000km (AT&T Bell Labs)

1993 Übertragungsdemstration von 10 Gbit auf Experimentalstrecken von 180 millionen (!) km Länge (in 500km Schleifen) von NTT Labs

1996 Fujitsu, Bell Labs, NTT Lab erreichen (unabhängig) 1 Tbit-Übertragungen

Aktuell will das europäische ESTHER-Programm vorhandene Netze für 10, 20, 40 Gbit-Übertragung über 500-700km aufrüsten



Kleine Soliton-Linkliste:
Vortragsdateien zum Download: (rightclick and "safe to...")

Folien: solitonen.pdf
Matlabcode: solitonen.m



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