Direct fiber excitation with a digitally controlled solid state laser source

Mode division multiplexing has been mooted as a future technology to address the impending data crunch of existing fiber networks. Present demonstrations delineate the light source from the mode creation steps, potentially inhibiting integrated solutions. Here we create fiber modes on demand with a digital laser and couple them directly into a few-mode fiber, where after transmission they are decoupled by modal decomposition. This is the first demonstration of an integrated source for encoding information into the spatial modes of light.