Thermoelectric transport perpendicular to layers in multiple barrier superlattice structures is investigated theoretically in two limiting cases of no lateral momentum scattering and strong scattering. In the latter regime when lateral momentum is not conserved, the number of electrons participating in thermionic emission will dramatically increase. The cooling power density is calculated using...

– Charge-ordered manganites of composition Pr1−x(Ca1−ySry)xMnO3 exhibit persistent photoconductivity upon exposure to X-rays. This is not always accompanied by a significant increase in the number of conduction electrons as predicted by conventional models of persistent photoconductivity. An analysis of the X-ray diffraction patterns and current-voltage characteristics shows that X-ray illumina...

The organization of nano-objects on macroscopic surfaces is a key challenge for the technological improvement and implementation nanotechnologies. For achieving operational functions, it required to assemble as controllable building blocks in highly ordered superstructures. Herein, we demonstrate growth self-organization metallic nanowires into hexagonal superlattices with tunable characteristi...

this review reports recent advances in metallic nanostructures based electrochemical sensors. interesting aspects of nps include size and shape-dependent interatomic bond distances, melting points, chemical reactivity, and optical and electronic properties. the small size of metallic nanostructures has allowed nanoscale electrochemical processes to be probed. electrochemical characteristics can...

We propose a dual-periodically domain-inverted structure for realizing an efficient third-harmonic generation at an arbitrary fundamental wavelength. The structure allows to couple two separate optical parametric processes, frequency doubling and frequency adding, through a cascaded quasi-phase-matched interaction, therefore, generate third-harmonic directly from a superlattice sample. As an ex...

We study a microscopic model for a disordered superlattice system, which simulates the effect of intrinsic alloy fluctuation on localization in alloy superlattices. Numerical investigation of scaling behavior of the localization length shows that excitations along and perpendicular to the superlattice axis undergo a localization transition at a nonzero critical disorder. Therefore, we contend t...

The (P,Q)-superlattice is a hyperstructure of the form (L, P ∨, Q ∧), where (L,∨,∧) is a lattice and the hyperoperations P ∨, Q ∧ are defined as follows: a P ∨ b . = a ∨ b ∨ P , a Q ∧ b . = a ∧ b ∧ Q. If the sets P,Q ⊆ L satisfy appropriate conditions, then (L, P ∨, Q ∧) is a superlattice. We examine the properties of the sets a P ∨ b and a Q ∧ b in connection to the properties of P,Q. Especial...

Monolithically integrated active cooling is an attractive way for thermal management and temperature stabilization of microelectronic and optoelectronic devices. SiGeC can be lattice matched to Si and is a promising material for integrated coolers. SiGeC/Si superlattice structures were grown on Si substrates by molecular beam epitaxy. Thermal conductivity was measured by the 3v method. SiGeC/Si...