DE HAAS - VAN ALPHEN EFFECT IN QUENCHED PLATINUM CRYSTALS.
| dc.contributor.advisor | Vuillemin, Joseph | en_US |
| dc.contributor.author | BOUFELFEL, ALI. | |
| dc.creator | BOUFELFEL, ALI. | en_US |
| dc.date.accessioned | 2011-10-31T17:01:14Z | |
| dc.date.available | 2011-10-31T17:01:14Z | |
| dc.date.issued | 1987 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10150/184187 | |
| dc.description.abstract | The oscillatory de Haas-van Alphen (DHVA) magnetization has been studied in Pt crystals containing more than 100 ppm vacancies. Magnetic fields as high as 75 kG were used. The oscillations were observed at temperatures as low as 0.45 k, and found to be strongly attenuated by the vacancies in this concentration range. The emphasis of this work is on the measurement of this attenuation for the purpose of studying conduction electron scattering due to single vacancies. Dingle (scattering) temperatures due to vacancies are reported for four cyclotron orbits with the field in a (110) plane, along with a new measurement of the cyclotron effective mass (m* = 2.31 ± 0.03) for the electron orbit 33° away from <100>. Vacancies were generated by quenching Pt single crystals from temperatures as high as 1730 °C in air, using a technique which minimizes the induced strain. The vacancy contribution to the electron scattering rate was separated by measuring the Dingle temperature in both quenched and annealed specimens which had been subjected to the same quenching process. The results suggest that there is only a moderate variation in this scattering rate over the s-p-like electron sheet of the Fermi surface. However, the scattering rate for the d-like open hole sheet, which contacts the Brillouin zone, is about 49% larger than that for the electron sheet. This anisotropy is attributed mainly to the lattice distortion around a vacancy and to the difference between the hole and electron wave-function symmetries. | |
| dc.language.iso | en | en_US |
| dc.publisher | The University of Arizona. | en_US |
| dc.rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. | en_US |
| dc.subject | Platinum -- Electric properties -- Defects. | en_US |
| dc.subject | Crystals -- Electric properties -- Defects. | en_US |
| dc.title | DE HAAS - VAN ALPHEN EFFECT IN QUENCHED PLATINUM CRYSTALS. | en_US |
| dc.type | text | en_US |
| dc.type | Dissertation-Reproduction (electronic) | en_US |
| dc.identifier.oclc | 699807020 | en_US |
| thesis.degree.grantor | University of Arizona | en_US |
| thesis.degree.level | doctoral | en_US |
| dc.identifier.proquest | 8726844 | en_US |
| thesis.degree.discipline | Physics | en_US |
| thesis.degree.discipline | Graduate College | en_US |
| thesis.degree.name | Ph.D. | en_US |
| dc.description.note | This item was digitized from a paper original and/or a microfilm copy. If you need higher-resolution images for any content in this item, please contact us at repository@u.library.arizona.edu. | |
| dc.description.admin-note | Original file replaced with corrected file July 2023. | |
| refterms.dateFOA | 2018-05-18T00:04:24Z | |
| html.description.abstract | The oscillatory de Haas-van Alphen (DHVA) magnetization has been studied in Pt crystals containing more than 100 ppm vacancies. Magnetic fields as high as 75 kG were used. The oscillations were observed at temperatures as low as 0.45 k, and found to be strongly attenuated by the vacancies in this concentration range. The emphasis of this work is on the measurement of this attenuation for the purpose of studying conduction electron scattering due to single vacancies. Dingle (scattering) temperatures due to vacancies are reported for four cyclotron orbits with the field in a (110) plane, along with a new measurement of the cyclotron effective mass (m* = 2.31 ± 0.03) for the electron orbit 33° away from <100>. Vacancies were generated by quenching Pt single crystals from temperatures as high as 1730 °C in air, using a technique which minimizes the induced strain. The vacancy contribution to the electron scattering rate was separated by measuring the Dingle temperature in both quenched and annealed specimens which had been subjected to the same quenching process. The results suggest that there is only a moderate variation in this scattering rate over the s-p-like electron sheet of the Fermi surface. However, the scattering rate for the d-like open hole sheet, which contacts the Brillouin zone, is about 49% larger than that for the electron sheet. This anisotropy is attributed mainly to the lattice distortion around a vacancy and to the difference between the hole and electron wave-function symmetries. |
