We derive an exact expression for the time-averaged electromagnetic energyinside a chiral dispersive sphere irradiated by a plane wave. The dispersionrelations correspond to a chiral metamaterial consisting of uncoupledsingle-resonance helical resonators. Using a field decomposition scheme and ageneral expression for the electromagnetic energy density in bi-anisotropicmedia, we calculate the Lorenz-Mie solution for the internal fields in a mediumthat is simultaneously magnetic and chiral. We also obtain an explicitanalytical relation between the internal electromagnetic field and theabsorption cross-section. This result is applied to demonstrate that strongchirality leads to an off-resonance field enhancement within weakly absorb.ingspheres.
展开▼
