Beam Instabilities in the Scale Free Regime

Institute for Complex Systems-CNR, Department of Physics, University Sapienza, Piazzale Aldo Moro 2, 00185 Rome, Italy.
Physical Review Letters (Impact Factor: 7.73). 01/2012; 108(3). DOI: 10.1103/PhysRevLett.108.033901
Source: arXiv

ABSTRACT The instabilities arising in a one-dimensional beam sustained by the
diffusive photorefractive nonlinearity in out-of-equilibrium ferroelectrics are
theoretically and numerically investigated. In the "scale-free model", in
striking contrast with the well-known spatial modulational instability, two
different beam instabilities dominate: a defocusing and a fragmenting process.
Both are independent of the beam power and are not associated to any specific
periodic pattern.

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