Conductivity maximum at low temperatures in metallic Si:P near the metal-insulator transition

A. Blaschette; A. Ruzzu; S. Wagner; H. v. Löhneysen

doi:doi:10.1209/epl/i1996-00264-2

Conductivity maximum at low temperatures in metallic Si:P near the metal-insulator transition DOI: 10.1209/epl/i1996-00264-2

Europhys. Lett, 36 (7), pp. 527-532 (1996)

Conductivity maximum at low temperatures in metallic Si:P near the metal-insulator transition

A. Blaschette, A. Ruzzu, S. Wagner and H. v. Löhneysen

Physikalisches Institut, Universität Karlsruhe, D-76128 Karlsruhe, Germany

(received 20 September 1996; accepted 17 October 1996)

PACS. 71.30 - Metal-insulator transitions.
PACS. 71.55 - Impurity and defect levels.
PACS. 72.20 - Conductivity phenomena in semiconductors and insulators.

Abstract:

High-resolution measurements of the electrical conductivity

below

of uncompensated Si:P with P concentration N above the critical concentration

are reported. In a narrow N range, roughly 10

above

actually exhibits a shallow maximum which rapidly shifts to higher T with decreasing N. These features, as well as the strong shift of the maxima towards higher T with magnetic field, are interpreted in terms of the suppression of the triplet particle-hole channel in the electron-electron interaction, arising from spin-flip scattering due to local magnetic moments.