Magnetic field-induced metal-insulator transition in diluted magnetic semiconductors

✍ Scribed by J. Jaroszyński; T. Dietl

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 707 KB
• Volume: 177
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(92)90152-i

✦ Synopsis

The role of electron-electron

Coulomb interactions and disorder is discussed vis-a-vis millikelvin experimental results for diluted magnetic semiconductors (DMS) in the vicinity of a metal-insulator transition (MIT) induced by a magnetic field. The critical behavior of conductivity tensor components and the dielectric susceptibility at the MIT in p-type Hg,_XMn,Te is compatible with the model in which the MIT is a result of quantum localization driven by disorder-modified electron-electron interactions.

At the same time the critical behavior of the Hall coefficient suggests that, in addition to electrons forming the Fermi liquid (FL) and undergoing localization at the MIT, there is a concentration of local electron s-spins, even on the metallic side of the MIT. The formation of these moments can presumably be described in terms of a disordered Hubbard-Mott model.