Temperature-dependent electron spin relaxation at the metal-to-insulator transition in n-type GaAs

verfasst von
P. Sterin, L. Abaspour, J. G. Lonnemann, E. P. Rugeramigabo, J. Huebner, M. Oestreich
Abstract

We present a detailed study of the temperature-dependent electron spin relaxation rate in n-type bulk GaAs in the regime of the metal-to-insulator transition at vanishing magnetic fields. The high-accuracy measurements reveal the longest spin relaxation time for a doping concentration slightly below the metal-to-insulator transition at a finite temperature of ∼7K. This global minimum of the electron spin relaxation rate results from a delicate interplay of hyperfine interaction, variable range hopping, and the Dyakonov-Perel mechanism. At higher doping densities, the Dyakonov-Perel mechanism becomes dominant at all temperatures changing with temperature gradually from the degenerate to the nondegenerate regime. A theoretical model including temperature-dependent transport data yields not only quantitative agreement with the experimental data but reveals additionally the gradual change from percolation-based large angle momentum scattering to ionized impurity small angle scattering. A simple interpolation of all available data allows to extract a maximal-possible spin relaxation time in n-doped, bulk GaAs for negligible external magnetic fields of ≈1μs.

Organisationseinheit(en)
Abt. Nanostrukturen
Abt. Atomare und molekulare Strukturen (ATMOS)
Institut für Festkörperphysik
Typ
Artikel
Journal
Physical Review B
Band
106
ISSN
2469-9950
Publikationsdatum
13.09.2022
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
Elektronische Version(en)
https://doi.org/10.1103/PhysRevB.106.125202 (Zugang: Geschlossen)