| Автор | R L Rosenbaum |
| Автор | M Slutzky |
| Автор | A Mobius |
| Автор | D S McLachlan |
| Дата выпуска | 1994-09-26 |
| dc.description | The metal-insulator transition in composite Al-Ge films has been extensively studied experimentally. Using the superconducting properties of clusters composed of aluminium grains in the presence of a magnetic field, the critical metallic volume fraction phi <sub>c</sub><sup>gp</sup> has been determined for the case of grain percolation (gp). Because the films investigated are composed of extremely small grains of Al partially coated with amorphous Ge, the critical volume fraction phi <sub>c</sub> takes on a comparably large value. Typically about 56 at.% Al. The low-temperature electrical conductivity data are examined using a number of criteria for phi <sub>c</sub>. Most of these criteria yield values phi <sub>c</sub> to within 1% of phi <sub>c</sub><sup>gp</sup>. However, one widely used criterion involving the fitting of the low-temperature conductivity data to a T<sup>1/2</sup> dependence, as suggested by the electron-electron interaction theory, was found to yield a significantly smaller value for phi <sub>c</sub>. Methods based on room-temperature data are also evaluated. These criteria yield phi <sub>c</sub> values that are within +or-1% of phi <sub>c</sub><sup>gp</sup>. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Various methods for determining the critical metallic volume fraction phi <sub>c</sub> at the metal-insulator transition |
| Тип | paper |
| DOI | 10.1088/0953-8984/6/39/018 |
| Electronic ISSN | 1361-648X |
| Print ISSN | 0953-8984 |
| Журнал | Journal of Physics: Condensed Matter |
| Том | 6 |
| Первая страница | 7977 |
| Последняя страница | 7992 |
| Аффилиация | R L Rosenbaum; Sch. of Phys. & Astron., Tel Aviv Univ., Israel |
| Аффилиация | M Slutzky; Sch. of Phys. & Astron., Tel Aviv Univ., Israel |
| Аффилиация | A Mobius; Sch. of Phys. & Astron., Tel Aviv Univ., Israel |
| Аффилиация | D S McLachlan; Sch. of Phys. & Astron., Tel Aviv Univ., Israel |
| Выпуск | 39 |
