Light and Complexity

In Graphene, the optical nonlinearity arises from the interaction of light with quasi-electrons moving in the peculiar band structure. Specific regimes, as massless relativistic propagation, which can be electromagnetically driven, allow a strong enhancement of the nonlinearity. This happens in certain spectral ranges, and particularly in the TeraHertz bandwidth.

Haiming Dong, Claudio Conti and Fabio Biancalana in http://arxiv.org/abs/1107.5803 investigate a novel class of self-trapped beams in the THz bandwidth, sustained by relativistically moving particles (Dirac fermions) in Graphene, a novel frontier between nonlinear optics and field-theory driven condensed-matter physics.