Synthesis and characterization of biocompatible nanodiamond-silk hybrid material.

A new hybrid material consisting of nanodiamonds (NDs) and silk has been synthesized and investigated. NDs can contain bright fluorescence centers, important for bioprobes to image biological structures at the nanoscale and silk provides a transparent, robust matrix for these nanoparticles in-vivo or in-vitro. The ND-silk hybrid films were determined to be highly transparent in the visible to near infrared wavelength range.

Reconfigurable photonic crystal waveguides created by selective liquid infiltration.

We experimentally demonstrate reconfigurable photonic crystal waveguides created directly by infiltrating high refractive index (n≈2.01) liquids into selected air holes of a two-dimensional hexagonal periodic lattice in silicon. The resulting effective index contrast is large enough that a single row of infiltrated holes enables light propagation at near-infrared wavelengths.

Measuring the dispersive properties of liquids using a microinterferometer.

Using a single-beam, compact interferometer, we measure the refractive index of liquids in the near IR. This highly compact device relies on a silica capillary with a 50 μm inner diameter: it uses a minimal volume of test liquid, isolates the liquid from the humid atmosphere, has broadband operation, and is inherently mechanically stable. These characteristics, in combination with straightforward data acquisition, make it particularly well-suited for measuring the optical properties in the near IR of a wide range of liquids.

Liquid crystal dynamics in a photonic crystal cavity created by selective microfluidic infiltration.

A microfluidic double heterostructure cavity is created in a silicon planar photonic crystal waveguide by selective infiltration of a liquid crystal. The spectral evolution of the cavity resonances probed by evanescent coupling reveals that the liquid crystal evaporates, even at room temperature, despite its relatively low vapor pressure of 5 × 10(-3) Pa. We explore the infiltration and evaporation dynamics of the liquid crystal within the cavity using a Fabry-Perot model that accounts for the joint effects of liquid volume reduction and cavity length variation due to liquid evaporation.