Collisions of Stable Spatio-Temporal Solitons

Silberberg 1 has recently shown that, in a homogeneous nonlinear Kerr material exhibiting anomalous group-velocity dispersion (AGVD), the propagation of the slowly-varying envelope of the electric-field can be described by a 3+1D nonlinear Schrodinger equation (NLSE): which is written in a group-velocity coordinate frame. The AGVD has been used to make temporal dispersion isomorphic to spatial diffraction which in turn gives rise to the possibility of simultaneous two-dimensional, radially symmetric self-focusing and temporal pulse compression resulting in a 3D soliton or “light-bullet”. This light-bullet is fully confined by nonlinear effects alone but exhibits the behavior of both temporal solitons in fibers and spatial solitons in slab waveguides.