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The interaction between proteins and hydration water stabilizes protein structure and promotes functional dynamics, with water translational motions enabling protein flexibility. Engineered solvent-free protein-polymer hybrids have been shown to preserve protein structure, function, and dynamics. Here, we used neutron scattering, protein and polymer perdeuteration, and molecular dynamics simulations to explore how a polymer dynamically replaces water. Even though relaxation rates and vibrational properties are strongly modified in polymer coated compared to hydrated proteins, liquidlike polymer dynamics appear to plasticize the conjugated protein in a qualitatively similar way as do hydration-water translational motions.

We present high resolution neutron spectroscopic investigations of polyethylene glycol matrices interacting attractively with neat SiO2 nanoparticles. We observe a very rich dynamical picture that significantly contradicts earlier conclusions on such systems. Investigating a short chain matrix we realized that a fraction of chains is attached at the nanoparticle surface suppressing completely its translational diffusion. Nevertheless these attached chains undergo an unchanged segmental dynamics seemingly forming a micellelike corona of chains attached with their OH end groups. Changing to methyl-terminated chains the picture changes drastically, now showing a tightly adsorbed layer that however is not glassy as often assumed but undergoes fast picosecond local dynamics. With the singular importance of end groups, mean field approaches are not applicable and future simulations should be redirected to model such unexpected phenomena.

We present our experimental demonstration of self-collimation inside a three-dimensional (3D) simple cubic photonic crystal at microwave frequencies. The photonic crystal was designed with unique dispersion property and fabricated by a high precision computer-controlled machine. The self-collimation modes were excited by a grounded waveguide feeding and detected by a scanning monopole. Self-collimation of electromagnetic waves in the 3D photonic crystal was demonstrated by measuring the 3D field distribution, which was shown as a narrow collimated beam inside the 3D photonic crystal but a diverged beam in the absence of the photonic crystal.

We experimentally demonstrate subwavelength resolution imaging at microwave frequencies by a three-dimensional (3D) photonic-crystal flat lens using full 3D negative refraction. The photonic crystal was fabricated in a layer-by-layer process. A subwavelength pinhole source and a dipole detector were employed for the measurement. By point-by-point scanning, we obtained the image of the pinhole source shown in both amplitude and phase, which demonstrated the imaging mechanism and subwavelength feature size in all three dimensions. An image of two pinhole sources with subwavelength spacing showed two resolved spots, which further verified subwavelength resolution.