Magnetotunneling spectroscopy with the field perpendicular to the tunneling direction of the transverse X electrons in GaAs/AlAs double-barrier structures under hydrostatic pressure

Journal article

We have measured the effect of in-plane magnetic field on tunneling resonances between transverse X states in GaAs/AlAs double-barrier structures under high hydrostatic pressure. Current-voltage and conductance-voltage measurements performed at pressures just beyond the type-II transition, and at fields up to 15 T, reveal clear field dependences of resonances originating from the Xt(1)→Xt(1) and Xt(1)→Xt(2) tunneling processes. Their behavior is consistent with a Lorenz force analysis, and therefore probes the in-plane electron dispersion around the X minima. Differences between measurements with the magnetic field oriented parallel to the [100] and [110] crystal axes reflect the anisotropy of the X minima, a first analysis indicating that the field dependence is dominated by the two Xt minima with large wave vectors perpendicular to the magnetic-field direction. In support of this, Schrödinger-Poisson modeling of the shift in bias position of the Xt(1) →Xt(2) resonance provides a value for the effective mass parallel to the Lorenz in-plane momentum vector which is consistent with the heavy principal effective mass of the X minima.

Authors: Smith, J; Klipstein, P; Grey, R; Hill, G

• Journal: Physical Review B - Condensed Matter and Materials Physics
• Volume: 58
• Issue: 8
• Pages: 4708-4712
• Publication date: 1998-08-15
• ISSN: 0163-1829
• Language: English