Stationary transmission through lattices with asymmetric nonlinear quadratic-cubic defect

Abstract

Stationary transmission through lattice chains with a nonlinear quadratic-cubic defect embedded at the center is investigated, with a particular focus on the asymmetric transmission under distinct symmetry breaking scenarios. We show that spectral regions with enhanced as well as suppressed diode-like operation for dimers can be achieved in twofold broken parity symmetry regimes. Dynamic simulations of a Gaussian excitation are studied and trapping at the central sites is probed for distinct asymmetry scenarios. We show that increasing quadratic nonlinearity enhances trapping at the dimer sites in the twofold asymmetry case. The formation of a strongly localized mode in the single asymmetry setting is also discussed.