You can find the online document here.
Publication appeared in Nature Photonics
Fluoresence image. To visualize the light evolution in the network, coherent laser light at a wavelength of 633 nm was launched into input modes 2 to 4 of an optical network. Colour centres are excited by the propagating beam and emit fluorescent light at a wavelength of 650 nm. The fluoresence signal is directly proportional to the propagating light intensity.