Electron-electron interaction and tunnel density of states at the Fermi level in high-density two-dimensional electron system
Abstract
The zero bias anomaly (ZBA) of the tunnel conductivity are investigated in the Al/δ - GaAs tunnel structure with 2D electron concentration in δ-layer to be equal to 3.6*1012 cm-2. We find that the dip (ZBA) in the tunnel density of states near the Fermi level EF reveals logarithmic dependence on the energy e in the range kT < epsilon< hslash/r. Here epsilon is the energy relative to Ef and r is the elastic relaxation time of 2D electrons. The depth of the ZBA is proportional to ln(T/T0) in the range T = 0.1 - 20 K. These results are in agreement with Aronov-Altshuler theory in which the correction to the 2D density of states is due to the effects of the electron-electron interaction in diffusion channel. The unusual behavior of the tunnel magnetoconductivity is observed.
- Publication:
-
Journal of Physics Conference Series
- Pub Date:
- November 2009
- DOI:
- 10.1088/1742-6596/193/1/012127
- Bibcode:
- 2009JPhCS.193a2127M