The fractional Fourier transform (FRFT) naturally exists in strongly nonlocal nonlinear (SNN) media and the propagation of optical beams in SNN media can be simply regarded as a self-induced FRFT. Through the FRFT technique the evolution of fields in SNN media can be conveniently dealt with, and an arbitrary square-integrable input field presents itself generally as a revivable higher-order spatial soliton which reconstructs its profile periodically after every four Fourier transforms. The self-induced FRFT illuminates the prospects for SNN media in new applications such as continuously tunable nonlinearity-induced FRFT devices.

• Received 14 June 2008

DOI:https://doi.org/10.1103/PhysRevA.78.043815