Portal de Periódicos da CAPES

Imaging of Friedel Oscillation Patterns of Two-Dimensionally Accumulated Electrons at Epitaxially Grown InAs(111) A Surfaces

2001; American Physical Society; Volume: 86; Issue: 15 Linguagem: Inglês

10.1103/physrevlett.86.3384

1092-0145

Kiyoshi Kanisawa, M. J. Butcher, Hiroshi Yamaguchi, Y. Hirayama,

Semiconductor Quantum Structures and Devices

The local density of states (LDOS) at the epitaxially grown InAs surface on a GaAs(111) A substrate were characterized using low-temperature scanning tunneling microscopy. Using dI/dV signal mapping, LDOS standing waves were clearly imaged at point defects and within nanostructures. Measurement of the wavelength as a function of bias voltage showed a nonparabolic dispersion relation for the conduction band. The observed wave features originate from the Friedel oscillations of the two-dimensional electron gas in the semiconductor surface accumulation layer.