Giant effective mass deviations near the magnetic field-induced minigap in double quantum wells

Technical Report · Thu Sep 01 04:00:00 EDT 1994

DOI:https://doi.org/10.2172/10184138· OSTI ID:10184138

Harff, N E ^[1]; Simmons, J A; Lyo, S K; Klem, J F ^[1]; Goodnick, S M ^[2]

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1. Sandia National Labs., Albuquerque, NM (United States)
2. Oregon State Univ., Corvallis, OR (United States)

The authors report major deviations in the electron effective mass m* near the partial energy gap, or minigap, formed in strongly coupled double quantum wells (QWs) by an anticrossing of the two QW dispersion curves. The anticrossing and minigap are induced by an in-plane magnetic field B{sub {parallel}} and give rise to large distortions in the Fermi surface and density of states, including a Van Hove singularity. Sweeping B{sub {parallel}} moves the minigap through the Fermi level, with the upper and lower gap edges producing a sharp maximum and minimum in the low-temperature in-plane conductance, in agreement with theoretical calculations. The temperature dependence of Shubnikov-de Haas (SdH) oscillations appearing in a tilted magnetic field yield a decreased m* {le} 1/3 m*{sub GaAs} near the upper gap edge, and indicate an increase in m* near the lower gap edge.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 10184138
• Report Number(s): SAND--94-2099C; CONF-9408155--6; ON: DE94018889; BR: GB0103012
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606
EFFECTIVE MASS
ELECTRIC CONDUCTIVITY
ELECTRONS
ENERGY GAP
ENERGY-LEVEL DENSITY
EXPERIMENTAL DATA
FERMI LEVEL
GALLIUM ARSENIDES
PHYSICAL PROPERTIES
SEMICONDUCTOR MATERIALS
SHUBNIKOV-DE HAAS EFFECT