Study of the metallic impurity band in n type GaAs

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7112358

Liu, S

Combined magneto-transport and far infrared spectroscopic measurements are used to probe the electronic states near the metal to insulator transition in n type GaAs. In transport measurements, the critical fields B[sub c] of the magnetic-field-induced metal-insulator-transition are determined. In far infrared transmission spectroscopy measurements, a feature corresponding to the donor 1s-2p transition is found to persist of the metallic side of metal insulator transition and provides evidence of the existence of a metallic impurity band near the metal insulator transition. The Shubnikov-de Haas oscillations in low temperature magneto transport measurements and the temperature dependence of infrared transmission spectra are studied in order to understand the transport and optical properties of this metallic impurity band. The activation energy and enhanced effective mass of this metallic impurity band are obtained from both transport and optical experiments. The far infrared transmission spectroscopic studies of high T[sub c] superconductor films are also reported.

• Research Organization: Maryland Univ., College Park, MD (United States)
• OSTI ID: 7112358
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606 -- Other Materials-- Physical Properties-- (1992-)
664000* -- Atomic & Molecular Physics-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ARSENIC COMPOUNDS
ARSENIDES
ELECTRIC CONDUCTIVITY
ELECTRICAL EQUIPMENT
ELECTRICAL INSULATORS
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
ELEMENTS
EQUIPMENT
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HIGH-TC SUPERCONDUCTORS
IMPURITIES
INFRARED SPECTRA
MAGNETORESISTANCE
MATERIALS
METALS
N-TYPE CONDUCTORS
PHYSICAL PROPERTIES
PNICTIDES
SEMICONDUCTOR MATERIALS
SHUBNIKOV-DE HAAS EFFECT
SPECTRA
SUPERCONDUCTORS