Observation of three-dimensional discrete-continuous x waves in photonic lattices.
We report on the generation of three-dimensional discrete X waves in a femtosecond laser-written waveguide array. Our measurements constitute the first experimental observation of temporally localized three-dimensional discrete-continuous entities. The X waves spontaneously emerge from a single-site excitation due to the discrete diffraction of the lattice and the normally dispersive as well as cubically nonlinear properties of the fused silica used as host material.
Institute of Applied Physics, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany. heinrich@iap.uni-jena.de
M
M
Heinrich
A
A
Szameit
F
F
Dreisow
R
R
Keil
S
S
Minardi
T
T
Pertsch
S
S
Nolte
A
A
Tünnermann
F
F
Lederer