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

authored by: 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.
Organisation(s): Nanostructures Section
Surfaces Science Section
Institute of Solid State Physics
Type: Article
Journal: Physical Review B
Volume: 106
ISSN: 2469-9950
Publication date: 13.09.2022
Publication status: Published
Peer reviewed: Yes
Electronic version(s): https://doi.org/10.1103/PhysRevB.106.125202 (Access: Closed)

BibTeX

@article{797fd6d499004e6ab412a0214db48c88,
title = "Temperature-dependent electron spin relaxation at the metal-to-insulator transition in n-type GaAs",
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.",
author = "P. Sterin and L. Abaspour and Lonnemann, {J. G.} and Rugeramigabo, {E. P.} and J. Huebner and M. Oestreich",
note = "Funding Information: This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy EXC-2123 QuantumFrontiers 390837967, Major instrumentation Initiative Project No. 315579172, and OE 177/10-2.",
year = "2022",
month = sep,
day = "13",
doi = "10.1103/PhysRevB.106.125202",
language = "English",
volume = "106",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Institute of Physics",
number = "12",
}