Thermoelectric studies of electronic properties of ferromagnetic GaMnAs layers

• Veröffentlicht in: Semiconductor Physics Quantum Electronics & Optoelectronics
• Datum: 2008
• Hauptverfasser: Osinniy, V., Dybko, K., Jedrzejczak, A., Arciszewska, M., Dobrowolski, W., Story, T., Radchenko, M.V., Sichkovskiy, V.I., Lashkarev, G.V., Olsthoorn, S.M., Sadowski, J.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України 2008
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/119060
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: Thermoelectric studies of electronic properties of ferromagnetic GaMnAs layers / V. Osinniy, K. Dybko, A. Jedrzejczak, M. Arciszewska, W. Dobrowolski, T. Story, M.V. Radchenko, V.I. Sichkovskiy, G.V. Lashkarev, S.M. Olsthoorn, J. Sadowski // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2008. — Т. 11, № 3. — С. 257-265. — Бібліогр.: 45 назв. — англ.

Thermoelectric power, electrical conductivity, and high field Hall effect were studied over a broad temperature range in ferromagnetic Ga₁₋xMnxAs epitaxial layers (0.015 ≤ x ≤ 0.06). Thermoelectric power analysis gives information about carrier transport mechanisms in layers with both metallic and non-metallic types of conductivity and allows determination of the Fermi energy and carrier concentration. At high temperatures (T > 70 K), the thermoelectric power in GaMnAs linearly increases with increasing temperature. That indicates the presence of a degenerate hole gas with the Fermi energy EF = 220 ± 25 meV, nearly independent of Mn content (for 0.02 ≤ x ≤ 0.05). At lower temperatures, GaMnAs layers with metallic-type conductivity show an additional contribution to the thermoelectric power with the maximum close to the Curie temperature.