We derive the electromagnetic energy density in a chiral metamaterial consisting of uncoupled single-resonance helical resonators. Both the lossless and absorptive cases are studied, and the energy density is shown to be positively definite. The key relation making the derivation successful is the proportionality between the magnetization and the rate of change of the electric polarization of the medium. The same time-domain formulation of energy density also applies to the bianisotropic medium proposed by Zhang et al. [ Phys. Rev. Lett. 102, 023901 (2009)]. This work may provide insights for studying time-dependent phenomena in metamaterials.
© 2011 Optical Society of America
Original Manuscript: September 1, 2010
Revised Manuscript: December 25, 2010
Manuscript Accepted: December 31, 2010
Published: February 23, 2011
Pi-Gang Luan, Yao-Ting Wang, Shuang Zhang, and Xiang Zhang, "Electromagnetic energy density in a single-resonance chiral metamaterial," Opt. Lett. 36, 675-677 (2011)