Resonant Γ–X–Γ tunneling in GaAs/AlAs/GaAs single barrier heterostructures at zero and elevated magnetic field

✍ Scribed by J.J. Finley; M.S. Skolnick; J.W. Cockburn; R. Teissier; R. Grey; G. Hill; M.A. Pate

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 139 KB
• Volume: 23
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1996.0301

✦ Synopsis

We report the observation of resonant tunneling and magneto-tunneling between states of different effective mass derived from zone centre ( ) and zone edge (X ) points of the Brillouin zone in single AlAs barrier diodes. The nature of the X states involved (longitudinal X z or transverse X xy ) is deduced from the observed resonances in the conductance versus bias characteristics at zero magnetic field (B). At finite B, the σ -V curves exhibit resonant magneto-tunneling with X z Landau levels (LL), whilst no evidence of resonances with X xy LLs is found. Clear observation of both LL index (in-plane momentum) conserving and non-conserving tunneling to X z allows the transverse effective mass in AlAs to be determined. As a consequence of the different effective masses, momentum-conserving tunneling is inhibited at B = 0, but is restored when high B is applied.