Electromagnetic Absorption in a Disordered Medium near a Photon Mobility Edge

A frequency regime in which electromagnetic waves in a strongly disordered medium undergo Anderson localization in $d=3$ dimensions is suggested. In the presence of weak dissipation in $d=2+\ensuremath{\epsilon}$ it is shown that the renormalized energy absorption coefficient increases as the photon frequency $\ensuremath{\omega}$ approaches a mobility edge ${\ensuremath{\omega}}^{*}$ from the conducting side as $\ensuremath{\alpha}\ensuremath{\sim}{({\ensuremath{\omega}}^{*}\ensuremath{-}\ensuremath{\omega})}^{\ensuremath{-}\frac{(d\ensuremath{-}2)\ensuremath{\nu}}{2}}$, $\ensuremath{\nu}=\frac{1}{\ensuremath{\epsilon}}$. This mobility edge occurs at a frequency compatible with the Ioffe-Regel condition.