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We report the hot photoexcited electron transfer across the coaxial interface of a cylindrical core-shell nanowire. Modulation of the transfer rates, manifested as a large tunability of the voltage onset of negative differential resistance and of voltage-current phase, is achieved using three different modes. The coupling of electrostatic gating, incident photon energy, and the incident photon intensity to transfer rates is facilitated by the combined influences of geometric confinement and heterojunction shape on hot-electron transfer, and by electron-electron scattering rates that can be altered by varying the incident photon flux, with evidence of weak electron-phonon scattering. Dynamic manipulation of this transfer rate permits the introduction and control of a continuously adjustable phase delay of up to ∼130° within a single nanometer-scale device element.

We demonstrate that ferroelectric (FE) polarizations oriented along the finite thickness direction in ultrathin films are enhanced by the introduction of extreme curvature, thereby suppressing the finite-size-driven evolution of the FE phase transition temperature T(C). The measured responses within individual nanoshells possess magnitudes nearly three times that for their planar counterparts while exhibiting finite curvature-dependent offsets in FE switching hystereses. In stark contrast to the expected scaling of a depression of T(C) with inverse thickness, results based on modified Landau-Ginzburg model calculations indicate geometric curvature-driven polarization gradients in ultrathin films result in significant increases in T(C).

The Greta oto, or the "glasswing butterfly", is a member of the Ithomiini tribe. Although rare among lepidopteran, the G. oto's wings are naturally transparent. To understand the material properties of natural transparency, the various structures on the surface of the wings, both the transparent and brown "veins" and wing parameter regions were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), reflectance spectrometry, transmission spectrometry and scanning probe microscopy (SPM) in order to investigate their local structure, periodic character, and electromechanical response. Nanosized protuberances in a highly ordered array were found on the surface of the transparent part similar to that of the "corneal nipple array" found in other insects as an antireflective device.

We report on the nanopatterning of double-bond-terminated silane (5-hexenyltrichlorosilane, HTCS) molecules on titania (TiO2) using conductive atomic force microscopy (AFM). The influences of tip electrostatic potential and scanning velocity, relative humidity and of the repeated application of voltage on the topographic height, width, and hydrophilic and hydrophobic contrast of the resultant patterns were investigated. Tip voltage and tip velocity ( v) were applied between -10 V