PDF Publication Title:
Text from PDF Page: 129
4. INVESTIGATION OF METAL-INSULATOR TRANSITION Table 4.1: Comparison of thin film strain imposed by the substrate and critical temperatures in temperature dependence of chosen Raman mode position. lattice mismatch, % 1.40% (tensile) 1.30% (tensile) 1.21% (tensile) 1.25% (tensile) 1.32% (tensile) 1.03% (tensile) 1.19% (tensile) regime below the transition an external trigger, such as temperature, the disproportionation decreases and at the same time the orbital overlap increases which leads to closing of energy gap between nickel and oxygen orbitals and increase in electronic conductivity in the material. The disproportionate distribution of electronic charges on the nickel sites creates at least two sites bearing charge described as 3 − δ and 3 + δ. Such charge distribution would influence the electronic structure of material, especially nickel electronic structure. If large enough, it should be observable in X-ray induced photoelectron spectra as two or more components to the main nickel multiplet line whose position and intensity vary with temperature. The energy gap in SNO compounds is considered to be a charge-transfer gap, it involves an electronic transfer between nickel and oxygen sites. Therefore oxygen electronic structure should also be taken into account. However due to inevitable surface contaminations the spectra are affected by the oxygen bearing surface contaminations and a detailed analysis is much more difficult. What is more, because in theory samarium does not take part in the metal-insulator transition, its electronic spectra should not vary with temperature. The spectra are also analyzed. The S-36AOw sample was measured between 123 K and 683 K at selected tem- peratures. The fitted XPS nickel spectra for 123 K, 303 K and 683 K are presented in figure 4.17. During the experiment the sample was measured again at room temperature. Low-temperature spectrum is characterized by high background and sample S-4AOw S-12AOw S-24AOw S-30AOw S-36AOw S-5Aw S-42Aw thickness, nm ap 26 3.786 99 3.790 169 3.793 193 3.792 216 3.789 80 3.800 520 3.794 T2, K 423 413-418 418 408 Raman shift difference, cm−1 18.2 8.6 3.5 3.4 which causes the electronic orbital separate. With 108PDF Image | Investigation of metal-insulator transition in magnetron sputtered samarium nickelate thin films
PDF Search Title:
Investigation of metal-insulator transition in magnetron sputtered samarium nickelate thin filmsOriginal File Name Searched:
Bilewska_Investigation_of_metal_insulator_transition_in_magnetron_sputtered_samarium.pdfDIY PDF Search: Google It | Yahoo | Bing
Sulfur Deposition on Carbon Nanofibers using Supercritical CO2 Sulfur Deposition on Carbon Nanofibers using Supercritical CO2. Gamma sulfur also known as mother of pearl sulfur and nacreous sulfur... More Info
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |