Controlled actuation of electroactive polymers with embedded high dielectric nanoparticles is theoretically analyzed. If the inclusions are placed randomly in the elastomer body, the composite always contracts along the direction of the applied field. For a simple cubic distribution of inclusions, contraction occurs if the applied field is directed along the [001] direction of the lattice. For ...

In 2008 the U.S. Department of Energy set a target of 20% wind energy by 2030. To date, induction-based turbines form the mainstay of this effort, but turbines are noisy, perceived as unattractive, a potential hazard to bats and birds, and their height hampers deployment in residential settings. Several groups have proposed that artificial plants containing piezoelectric elements may harvest wi...

In the final few years of his life, Julian Schwinger proposed that the “dynamical Casimir effect” might provide the driving force behind the puzzling phenomenon of sonoluminescence. Motivated by that exciting suggestion, we have computed the static Casimir energy of a spherical cavity in an otherwise uniform material. As expected the result is divergent; yet a plausible finite answer is extract...

Transient grating experiments performed with evanescent fields resulting from total internal reflection at an interface between a polar absorbing solution and an apolar transparent solvent are described. The time evolution of the diffracted intensity was monitored from picosecond to millisecond time scales. The diffracted signal originates essentially from two density phase gratings: one in the...

The ability of time-resolving enthalpy (∆H) and structural volume (∆V) changes in the nanoto μs time range offered by laser-induced optoacoustic spectroscopy (LIOAS) opens the possibility of a stepwise thermodynamic analysis of chromophore-medium interactions upon photoinduced reactions in biological systems. We applied LIOAS to biological photoreceptors, as well as to model systems, with the p...

Experiments measuring the transmission of 5 nanosecond (FWHM), 532 nm pulses through an optical limiter using two different nonlinear materials at two separate focal planes show by far the highest dynamic-range measured to date. This cascaded focus, f/5 optical limiter combines self focusing and consequent nonlinear scattering in CS2, with reverse saturable absorption in lead-phthalocyanine (Pb...

Temp erature dependence s of the linear dimension L ( T ) and spontaneous polari zati on P s( T ) for tri glycine sulphate and glycine posphite single crystals have been measured in the same run of temp erature. A decrease in the spontaneous electrostriction coe£cient Q L of both crystals studied is displayed w hen approaching the corresp ondi ng phase transition point T c . A temp erature dep ...

Pulsed plasmas in liquids exhibit complex interaction between three phases of matter (liquids, gas, plasmas) and are currently used a wide range applications across several fields, however significant knowledge gaps our understanding plasma initiation hinder additional application control; this area research lacks comprehensive predictive model. To aid progress experimentally, here we present t...