Ultrafast Proton Transfer in Polymer Blends Triggered by Shock Waves.

We describe ultrafast proton transfer in the ground electronic state triggered by the use of shock waves created by high-speed impacts. The emission of Nile Red (NR), a polarity sensing dye, was used to probe the effects of shock compression in a series of polymers, including polymer Brønsted bases blended with organic acid proton donors. NR undergoes a shock-induced red-shift due to an increase both in density and in polymer polarity.

Laser-driven flyer plates for shock compression science: launch and target impact probed by photon Doppler velocimetry.

We investigated the launch and target impact of laser-driven Al flyer plates using photon Doppler velocimetry (PDV). We studied different flyer designs launched by laser pulses of different energies, pulse durations and beam diameters, that produced km s(-1) impacts with transparent target materials. Laser-launching Al flyers 25-100 μm thick cemented to glass substrates is usually thought to involve laser vaporization of a portion of the flyer, which creates many difficulties associated with loss of integrity and heating of the flyer material.

Demonstration of angle-dependent Casimir force between corrugations.

The normal Casimir force between a sinusoidally corrugated gold coated plate and a sphere was measured at various angles between the corrugations using an atomic force microscope. A strong dependence on the orientation angle of the corrugation is found. The measured forces were found to deviate from the proximity force approximation and are in agreement with the theory based on the gradient expansion including correlation effects of geometry and material properties.

Demonstration of the Casimir force between ferromagnetic surfaces of a Ni-coated sphere and a Ni-coated plate.

We demonstrate the Casimir interaction between two ferromagnetic boundary surfaces using the dynamic atomic force microscope. The experimental data are found to be in excellent agreement with the predictions of the Lifshitz theory for magnetic boundary surfaces combined with the plasma model approach. It is shown that for magnetic materials the role of hypothetical patch potentials is opposite to that required for reconciliation of the data with the Drude model.

Reduction of the Casimir force from indium tin oxide film by UV treatment.

A significant decrease in the magnitude of the Casimir force (from 21% to 35%) was observed after an indium tin oxide sample interacting with an Au sphere was subjected to the UV treatment. Measurements were performed by using an atomic force microscope in high vacuum. The experimental results are compared with theory and a hypothetical explanation for the observed phenomenon is proposed.