Liquid-infiltrated photonic crystals: Ohmic dissipation and broadening of modes

The pronounced light–matter interactions in photonic crystals make them interesting as opto–fludic “building blocks” for lab–on–a–chip applications. We show how conducting electrolytes cause dissipation and smearing of the density–of–states, thus altering decay dynamics of excited bio–molecules dissolved in the electrolyte. Likewise, we find spatial damping of propagating modes, of the order dB/cm, for naturally occurring electrolytes such as drinking water or physiological salt water.