Magnetotunneling spectroscopy of one-dimensional wires

We present results of a detailed study of equilibrium magnetotunneling between an array of independent identical one-dimensional wires and a two-dimensional electron gas. From the tunneling differential conductance, measured as a function of the in-plane magnetic field, we find directly the number of occupied one-dimensional subbands, the subband energies, and the wave functions as a function of the strength of confinement in these wires. As many as 14 one-dimensional subbands were probed. We show that an analysis of our results based on the Bardeen tunneling Hamiltonian formalism allows the determination of the functional form of one-dimensional confining potentials. We give two examples, one for a narrow wire and one for a wide wire.