Huber, Michael and Grayson, M. and Rother, Martin and Deutschmann, R. A. and Biberacher, W. and Wegscheider, Werner and Bichler, Max and Abstreiter, Gerhard
Tunneling in the quantum Hall regime between orthogonal quantum wells.
Physica E Low-dimensional Systems and Nanostructures 12 (1-4), pp. 125-128.
We present experimental investigations of tunneling between two quantum wells forming a T-shaped structure. At zero magnetic field we observe a nonlinear tunnel characteristic with clearly pronounced negative differential resistance. With magnetic field B, both quantum wells can independently be set in a quantum Hall state. We demonstrate spectroscopy of Quantum Hall bulk states in one B field orientation, and spectroscopy of edge states with the orthogonal orientation. The observed features can be explained assuming that transverse momentum is conserved during tunneling.