Gap soliton gating, dissociation, and retrieval via defect mode excitation in a resonant photonic crystal

Abstract

There has been a recent resurgence of interest in photonic crystals (PC) with resonant nonlinearity, mainly driven by dramatic advances in manufacturing InGaAs/GaAs Bragg periodic multiple quantum well structures and rare-earth doped AlGaAs/GaAs nanostructures [1][2][3][4]. This suggest that such building block of future optical computing as gap soliton (GS) might be experimentally feasible at moderate level of light intensity ∼ 10 MW/cm 2 . Recently, we have proposed an effective mean of control over these solitons when a defect associated with a weak linear excitation or incoherent pump inside a resonant photonic crystal (RPC) modifies GS propagation [5][6][7]. It turns out that the periodicity breakup is unnecessary for the GS to be trapped inside the RPC because a weak non-propagating field creates a potential that acts as a phase-sensitive trap. In this Letter, using the results of a detailed and extensive theoretical study of excitation trapping inside RPCs [6,7], a further interesting consequences of inverting a small length inside a RPC is explored: all-optical filtering and memory cell effect.First of all, relevant expressions from the theory are abstracted and adapted. Assuming a collinear, distributed feedback two-wave interaction in a medium of periodically positioned two-level atoms, the governing Maxwell-Bloch equations take the form [5-7]: , P x t