Thermoelectric power of the two-dimensional electron gas in GaAs-Al/sub x/Ga/sub 1-x/As heterostructures

Journal Article · Sun Jun 15 04:00:00 EDT 1986 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.33.8238· OSTI ID:5700352

Davidson, J S; Dahlberg, E D; Valois, A J; Robinson, G Y

Detailed experimental studies have been made of the thermoelectric properties of the two-dimensional electron gas in single-interface GaAs-Al/sub 0.3/Ga/sub 0.7/As heterostructures. At temperatures below 10 K the zero-applied-magnetic-field thermopower is linear in temperature and is consistent with the diffusion thermopower for a two-dimensional electron gas. In the presence of a quantizing magnetic field the thermopower tensor is not diagonal and measurements of both components of the thermoelectric tensor have been made as functions of temperature and applied magnetic field. In the samples which have been studied, the experimental results are consistent with Gaussian-broadened Landau levels. At higher temperatures the thermopower is found to decrease with increasing temperature. This effect occurs both in zero field and in the presence of a magnetic field. This effect is similar to what is anticipated if phonon drag were present except the sign of this extra contribution is opposite to that observed in bulk n-type GaAs.

• Research Organization: School of Physics and Astronomy, University of of Minnesota, Minneapolis, Minnesota 55455
• DOE Contract Number: AC02-81ER10887
• OSTI ID: 5700352
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 33:12; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON GAS
EPITAXY
EXPERIMENTAL DATA
FLUIDS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GASES
HETEROJUNCTIONS
INFORMATION
JUNCTIONS
MAGNETIC FIELDS
MOLECULAR BEAM EPITAXY
NUMERICAL DATA
PHYSICAL PROPERTIES
PNICTIDES
SEMICONDUCTOR JUNCTIONS
SHUBNIKOV-DE HAAS EFFECT
TEMPERATURE DEPENDENCE
THERMOELECTRIC PROPERTIES
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE