Nonlinear Vertical Resonant Tunneling in Double Quantum Wells in an In-Plane Magnetic Field

We present a theory and data for the tunneling current between two electron-gas layers separated by a wide barrier in an in-plane magnetic field $B$. The electron gases are separately in equilibrium with their chemical potentials displaced by the bias energy $V$. The observed tunneling current and the differential conductance show interesting domain structure on the $B-V$ plane. Our theory, based on incoherent tunneling and the $B$-induced displacement of the energy dispersion curves, generates a similar domain structure, yielding excellent agreement with the data from GaAs/Al$_x$Ga$_{1-x}$As double quantum wells. An extension of the current result to 2D-1D tunneling will be discussed. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U.S. DOE under contract DE-AC04-94AL85000.