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We experimentally observe anomalous wavepacket evolution in a realization of a one-dimensional finite binary Anderson model in the presence of short-range correlations. To this end, we employ weakly-coupled optical waveguides with propagation constants ε1 and ε2. The correlations enforce the creation of dimers, i.e. two adjacent waveguides with the same ε, randomly placed along the lattice. A transition from a ballistic to a superdiffusive wavepacket expansion and, eventually, to localization is observed as the contrast between the two propagation constants increases. [ABSTRACT FROM AUTHOR]

We present, theoretically and experimentally, the observation of the Rashba effect in photonic lattices, where the effect is brought about by an artificial gauge field, induced by the geometry of the system. In doing that, we demonstrate a particular form of coupling between pseudospin and momentum, resulting in spin-dependent shifts in the spectrum. Our system consists of two coupled, oppositely tilted waveguide arrays, where the evolution of an optical beam allows for probing the dynamics of the evolving wave packets, and the formation of spectral splitting. We show that the Rashba effect can be amplified or decreased through optical nonlinear effects, which correspond to mean-field interactions in various systems such as cold-atom lattices and exciton-polariton condensates. [ABSTRACT FROM AUTHOR]