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Biomaterials offer opportunities for devices that operate at the interface of the biological and technological worlds. Devices such as silk-based photonic crystals, lasers, wireless antennas and resorbable electronics will be described as examples of the possibilities that this water-processed, biocompatible material offers.

Voids were created inside biocompatible, optically transparent silk fibroin hydrogels via multi-photon ablation in arbitrary 3D patterns at a maximum depth of nearly 1 cm without exogenous photoinitiators.

Biocompatible waveguides were created by encapsulating a silk fibroin film (n=1.54) inside a silk fibroin hydrogel (n=1.34). We found these structures capable of guiding light in tissue.

The use of silk as a material for technological applications has been introduced over the past few years. We will overview how purified silkworm silk can be reassembled, among other things, in a multitude of high quality, biocompatible micro- and nanostructured optical and optoelectronic elements.

We demonstrate high throughput imprinting of nanophotonic structures on silk films using a silk template, allowing for positive and negative pattern fabrication. Induced beta-sheet crystallinity increases their durability and biological applicability.

In this paper, we present a series of fully implantable and resorbable metamaterial devices constituted by magnesium and silk protein with controllable degradation rate, which can be used for biological tracking and sensing applications.

Hybrid plasmonic-photonic crystal (HPPC) composed of biopolymer-silk and silver film offers label free refractive index sensing. Detectability of the sensor is enhanced by surface plasmon. The sensor shows a sensitivity of 281 nm/RIU.

We present a free-standing micro-prism array device entirely constituted by silk protein showing enhanced optical reflectivity, which can be used to monitor drug delivery while slowly degrading to surrounding tissues with no adverse biological effects.

We present microfluidic integration of a novel optical sensing technique based on distinctive structural color modifications in aperiodic nano-structures. The liquid-induced index sensitivity of the proposed devices is quantified by autocorrelation analysis in the visible spectral range.

Azobenzene modified silk, a biocompatible material suitable for applications in biomedicine is shown to display photo-effects such as optically induced birefringence, suitability as a holographic recording material and photoinduction of surface relief features.

A novel optical sensing technique based on distinctive colorimetric signatures and spectral shifts of deterministic aperiodic arrays is demonstrated by protein monolayer sensing in the visible spectral range using inexpensive dark-field spectroscopy and autocorrelation analysis.

Short interaction lengths limit the application of infrared absorption spectroscopy to the study monolayer thickness films. We employ periodic infrared antenna arrays to obtain 10(4)-10(5) enhancement of protein absorption signals corresponding to zepto-mole sensitivity.

We demonstrate photomechanical actuation by measuring the variation of the diffracted excitation light source.

We demonstrate low threshold, octave spanning spectrally flat, supercontinuum generation in a short length of tapered SF6 glass photonic crystal fiber. The short fiber is held stably and robustly with a polydimethyl-siloxane (PDMS) matrix.

This paper presents a label free colorometric sensor fabricated by rapidly imprinting silk fibroin thin films with periodic nanoholes. The fabricated sensor is sensitive to index variations of Δn = 0.007.

Using XFROG and FROG we observe the details of supercontinuum formation and soliton dynamics in highly-nonlinear SF6 photonic crystal fibers. At high input powers in the anomalous dispersion region the solitons display substantial temporal jitter.

Strong guiding and multimode nature of cobweb fibers allow for intermodally phase-matched harmonic generation at visible-UV wavelengths. We compare experimental and theoretical harmonics' spectra to show the influence of cross-phase modulation during harmonic generation

Cross-correlation frequency-resolved optical gating is used to probe the dynamics of a femtosecond pulse in a double-zero dispersion point photonic crystal fiber. Soliton attraction to the second zero-dispersion point and multiple-soliton interaction are observed.

We present time-resolved X-FROG measurements of soliton dynamics near the second zero-dispersion point in microstructured fibers. Stabilization of the soliton against the Raman self-frequency shift by recoil from Cherenkov radiation emitted in the normal-dispersion region is observed

The use of conveniently available ultrafast pulses in optical fibers and in photonic crystal fibers has generated a renaissance of interest in nonlinear phenomena of guided light spanning from propagation dynamics to supercontinuum generation. A review of some of these results will be presented.

By coupling femtosecond pulses at λ=1.55 microns in a one meter segment of photonic crystal fiber we observe simultaneous generation of third harmonic frequencies from both the fundamental and its self-shifted Raman component, whereas no second harmonic signal is detected.

Adaptive control is used to defeat nonlinear effects that severely distort ultrafast pulses during propagation through optical fibers.

We demonstrate analysis of amplitude-shaped ultrashort pulses using a compact folded shaper at a wavelength λ=1.55 µm using a single-shot geometry SHG- FROG setup. Sensitivity to pulses having energies of less than 20 pJ is reported for this geometry, making this method applicable to studies of the nonlinear effects of ultrashort pulse propagation in fibers.

Summary form only given. Frequency-resolved optical gating (FROG) has gained prominence as a technique for characterizing ultrashort pulses. FROG consists of a spectrally resolved autocorrelation of the pulse to be measured. We have demonstrated phase reconstruction from FROG using a genetic algorithm. Even though only the most basic evolutionary operators were used, the genetic algorithm returned lower FROG errors on certain types of experimental and theoretical pulses then the standard composite iterative algorithm.