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Quenching of the exciton luminescence of GaN epitaxial films and GaN/AlGaN quantum wells in an electric field is observed and attributed to impact ionization of excitonic states by hot electrons. It is found that impurity scattering rules the momentum rela ...
A ferroelectric cathode is employed in a cyclotron-resonance maser (CRM). The CRM oscillator device operates at similar to 7 GHz, near the cutoff frequency of a hollow cylindrical cavity. The cathode is made of a PLZT 12/65/35 ceramic with high-dielectric ...
The impact ionization of excitonic states is studied in epitaxial GaN films and GaN/AlGaN quantum well structures. The investigation is carried out by optical methods involving the observation of quenching of the exciton photoluminescence under an applied ...
This invention relates to a device for emitting addressable locations comprises parallel spaced-apart first conductors (10) intersecting with parallel spaced-apart second conductors (11). The intersecting first and second conductors define addressable loca ...
The surface properties and the electrochem. behavior of a fluorinated B-doped diamond (F-BDD) electrode prepd. by plasma treatment in CF4-He mixt. was studied by XPS and cyclic voltammetry in acidic media. The results showed C-F bonding (C-CF and C-F) on t ...
The internal electric field in multilayer organic light-emitting diodes (OLEDs) is investigated using a combination of experimental measurement and numerical device modeling. This approach results in a detailed understanding of the functioning of a multila ...
Secondary fly ash, resulting from thermal treatment processes, leads to a highly concd. chloride soln. with Cu, Pb, Cd and Zn as main heavy metals when dissolved in water. The selective electrodeposition of these heavy metals was studied. The goal was to r ...
Impact ionization of exciton states in epitaxial GaN films and GaN/AlGaN quantum-well structures was studied. The study was done using an optical method based on the observation of exciton photoluminescence quenching under application of an electric field. ...
We discuss a novel approach to measure the electron phase-relaxation length and femtosecond lifetimes at surfaces. It relies on the study of the spatial decay of quantum interference patterns in the local density of states (LDOS) with the STM. The method h ...
The inertness and unique electrochem. properties of diamond present great potential for a variety of applications in aggressive environments. Preliminary results showed the widest known electrochem. window before water decompn., allowing new possibilities ...
