Switching is obtained using nonlinear optical effects when two or more signals are combined.
The nonlinear effects are particular evident due to the high-powered acoustic waves involved.
For the nonlinear effect to occur, relatively high intensity ultrasonics are required.
They result from a delicate balance between acoustic dispersion and nonlinear effects.
This is done by using a nonlinear effect to modify the dipole response of a medium to a signal or "probe" field.
This allows nonlinear optical effects to be seen at low powers.
This effect, strongly nonlinear, was unexpected but led to a very effective system for streamer guidance.
Usually, a typical magnitude value of the acoustic pulse will be small, and for long propagation nonlinear effects could become important.
However, nonlinear effects can give rise to a nonzero average.
An important aspect of their work involves the nonlinear effect of trend.