title: Topological solitons as addressable phase bits in a driven laser.
abstract: Optical localized states are usually defined as self-localized bistable packets of light, which exist as independently controllable optical intensity pulses either in the longitudinal or transverse dimension of nonlinear optical systems. Here we demonstrate experimentally and analytically the existence of longitudinal localized states that exist fundamentally in the phase of laser light. These robust and versatile phase bits can be individually nucleated and canceled in an injection-locked semiconductor laser operated in a neuron-like excitable regime and submitted to delayed feedback. The demonstration of their control opens the way to their use as phase information units in next-generation coherent communication systems. We analyse our observations in terms of a generic model, which confirms the topological nature of the phase bits and discloses their formal but profound analogy with Sine-Gordon solitons.
authors.affiliation: Université de Nice-CNRS UMR 7335, Institut Non Linéaire de Nice, 1361 route des lucioles, 06560 Valbonne, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Garbin
authors.affiliation: Departament de Física, Universitat de les Illes Baleares, C/Valldemossa km 7.5, 07122 Mallorca, Spain.
authors.forename: Julien
authors.initials: J
authors.lastname: Javaloyes
authors.affiliation: Université de Nice-CNRS UMR 7335, Institut Non Linéaire de Nice, 1361 route des lucioles, 06560 Valbonne, France.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Tissoni
authors.affiliation: Université de Nice-CNRS UMR 7335, Institut Non Linéaire de Nice, 1361 route des lucioles, 06560 Valbonne, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Barland