Advanced Undergraduate Laboratory

Department of Physics

University of Toronto

SOL: Solitons

A Soliton is a very general and ubiquitous kind of nonlinear wave. Unlike a normal linear wavetrain, a soliton is tightly localized and has a single maximum, hence the name ``solitary wave", or soliton. It retains its form while propagating and even survives collisions with other solitons. These properties are made possible by a balance between amplitude nonlinearity (which makes larger amplitude waves move faster) and dispersion (which makes wavetrains of different frequency move at different speeds). Solitons occur as surface waves on fluids (as in this experiment), in nonlinear optical pulses in fibers, in theories of signal propagation in nerve fibers, in Bose-Einstein condensates, and in many other physical and mathematical contexts.

This experiment is related to research carried out in Prof. Stephen Morris's Experimental Nonlinear Physics Group.


Write-Up in PDF Format.

(This experiment was new in 2018).

A movie showing a collection of reflecting solitons:

Additional resources:

Photo of soliton propagting in a long tank of red water.

A soliton progagating in a long tank: water, dyed red.

Last updated on 27 July 2021