Sign flips, crossovers, and spatial inversions in surface plasmon resonance across a chiral-metal interface

We consider the surface plasmon resonance established along an interface between a metal and a chiral medium (chiral case). Resulting solutions are compared with those obtained for a metal-dielectric interface (achiral case). We found that the chiral case exhibits either larger or smaller phase speeds than the achiral case due to the energy redistribution between translation and rotation. For a loss-free system, we found crossovers among the dispersion curves and spatial inversions in field profiles. These features are associated with anti-symmetric spin flips with respect to medium chirality. The short-wavelength limit leads to an upper bound on the medium chirality. (c) 2023 Optica Publishing Group

Automated summary

We investigate the surface plasmon resonance in a metal-chiral medium interface and compare it with the metal-dielectric interface. The chiral case exhibits either larger or smaller phase speeds compared to the achiral case due to energy redistribution between translation and rotation. In a loss-free system, there are crossovers among dispersion curves and spatial inversions in field profiles, which are associated with anti-symmetric spin flips with respect to medium chirality. The short-wavelength limit establishes an upper bound on medium chirality.