Optical characterization of silicon on insulator photonic crystal nanocavities infiltrated with colloidal PbS quantum dots

The authors present the fabrication of silicon on insulator (SOI) membrane nanocavities for use as sensitive optical biosensors and investigations of their optical properties. Simulations illustrate the evolution of the cavity mode frequency as a function of structural parameters. The SOI nanocavities were characterized using μ -photoluminescence spectroscopy by doping the photonic crystals with colloidal PbS quantum dots embedded in a polymer matrix. Experiments lead to cavity mode quality factors of Q=800±35 and the dependence on geometric parameters is in excellent agreement with our calculations.