Propagation of light through amplifying honeycomb photonic lattice

TL;DR

This paper investigates light propagation in an amplifying honeycomb photonic lattice, revealing a critical length where the system transitions from amplification to generation, with enhanced transmission and reflection at this point.

Contribution

It introduces a non-Hermitian Dirac equation model for the system and identifies a critical length for the amplifier-generator transition in the lattice.

Findings

Existence of a critical length for amplification to generation transition

Enhanced transmission and reflection at the critical length

Amplification sensitivity to incident light direction and region thickness

Abstract

We consider light propagation through a ballistic amplifying photonic honeycomb lattice below the lasing threshold. Two sublattices of the system are formed by the wave-guides with different complex dielectric permittivities, which results in the non-Hermitian Dirac equation for electromagnetic field. We reveal that there exists a critical length of the amplifying region for which the photonic lattice exhibits an amplifier to generator transition. The transmission and reflection probabilities at the normal angle of incidence are strongly enhanced at a critical length of the system. We also comment on the sensitivity of amplification to the direction of incident light and the thickness of the amplifying region.