Authors: S Li Y Y Tay C Q Sun
Publish Date: 2007/03/27
Volume: 21, Issue: 1-4, Pages: 91-98
Abstract
Physical properties of electronic and photonic materials can be significantly modified by partial altervalent/aliovalent chemical substitutes The modification arises from the subtle interplay between the competing/cooperating effects of the electron and lattice structural variations which are induced by the different charge and atomic radii of the substituents To understand these effects it is necessary to isolate the electronic and crystallographic contributions to the particular physical property to arrive at a fundamental understanding of the underlying dominant mechanism Intrinsic properties amplified nanomaterials/nanoparticles is a newly developed technique which can experimentally discriminate lattice structural effects from electronic contributions to physical properties by exploiting the nanosize dependence of lattice structure to modify the structural parameters without resorting to chemical doping In this work we demonstrate a separation of structural and electronic effects on superconducting critical temperatures T c of MgB2 and YBa2Cu3O7x and also on emission behavior of ZnO The results show that the superconductivity of MgB2 is extremely sensitive to lattice parameter variation while T c of YBa2Cu3O7x is more sensitive to electronic structure The effects of the lattice and electronic structures on the emission behavior of ZnO are complex and the structural variations make different contributions to the behavior in the particular conditions
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