3: Squeezing the soliton
Output energy (top) and squeezing (bottom) plotted as a function of the input energy for a 90/10 asymmetric fibre-based interferometer loop. The output-pulse energy shows an optical-limiting effect at input energies of 53 picojoules and 83 picojoules. The y-axis in the lower graph is the photocurrent noise power in a photodiode detector relative to the shot noise (horizontal line). The quantum fluctuations are reduced below the shot-noise level (i.e. "squeezed") at the input energies for which optical limiting occurs. (From Schmitt et al.)