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71.
In this paper we report on the structural, electrical and optical characteristics of unintentionally doped ZnO films grown on a-plane sapphire substrates using the Filtered Cathodic Vacuum Arc (FCVA) technique. The resulting films showed considerable promise for device applications with properties including high transparency, moderate intrinsic carrier concentrations (1017–1019 cm−3), electron mobilities up to 30 cm2/Vs, low surface roughness (typically <2% of film thickness) and well-structured photoluminescence. Post-annealing in oxygen at temperatures up to 800 °C produced significant improvements in the properties of these films. Silver oxide Schottky diodes fabricated on FCVA ZnO showed ideality factors as low as 1.20 and good sensitivity to ultraviolet light.  相似文献   
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This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported.  相似文献   
75.
Composite materials are prone to a wide range of defects and damage which may significantly reduce their residual strength. Of the various types of defects possible, interply delaminations arising from in-service damage are probably the most insiduous because of their effects on residual compressive strength and difficulties associated with their detection. In this study, a finite element analysis of the self similar growth of a circular delamination in a compressed laminate is undertaken, and the results are compared with an analytical solution.  相似文献   
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We study the role of particle transport and evaporation on the phase separation of an ultracold, spin-polarized atomic Fermi gas. We show that the previously observed deformation of the superfluid paired core is a result of evaporative depolarization of the superfluid due to a combination of enhanced evaporation at the center of the trap and the inhibition of spin transport at the normal-superfluid phase boundary. These factors contribute to a nonequilibrium jump in the chemical potentials at the phase boundary. Once formed, the deformed state is highly metastable, persisting for times of up to 2?s.  相似文献   
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We demonstrate that when, and only when, the biaxial stress is increased above a critical value of 6+/-1 GPa during the growth of a carbon film at room temperature, tetrahedral amorphous carbon is formed. This confirms that the stress present during the formation of an amorphous carbon film determines its sp;{3} bonding fraction. In the vicinity of the critical stress, a highly oriented graphitelike material is formed which exhibits low electrical resistance and provides Ohmic contacts to silicon. Atomistic simulations reveal that the structural transitions are thermodynamically driven and not the result of dynamical effects.  相似文献   
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Potential energy curves for the 4Σ+u, 4Πg and 6Σ+g states of N+2 that dissociate to N (4S0) and N+(3P), have been determined from a complete active space self-consistent field calculation. The 6Σ+g state is found to be significantly bound (De = 2.68 eV) with a minimum at 1.72 Å.  相似文献   
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