  We investigate the electromagnetic field concentration between two
nearly-touching inclusions that possess high-contrast electric permittivities
in the quasi-static regime. By using layer potential techniques and asymptotic
analysis in the low-frequency regime, we derive low-frequency expansions that
provide integral representations for the solutions of the Maxwell equations.
For the leading-order term $\bE_0$ of the asymptotic expansion of the electric
field, we prove that it has the blow up order of $\epsilon^{-1} |\ln
\epsilon|^{-1}$ within the radial geometry, where $\epsilon$ signifies the
asymptotic distance between the inclusions. By delicate analysis of the
integral operators involved, we further prove the boundedness of the
first-order term $\bE_1$. We also conduct extensive numerical experiments which
not only corroborate the theoretical findings but also provide more discoveries
on the field concentration in the general geometric setup. Our study provides
the first treatment in the literature on field concentration between
nearly-touching material inclusions for the full Maxwell system.
