TUNNELING BETWEEN SPIN POLARIZED EDGE STATES STUDIED AT HIGH MAGNETIC FIELDS.

We utilize the tunneling between edge states of the lowest Landau level to study the behavior of the spin splitting in a wide range of magnetic fields up to 28 T. We find that the Zeeman energy with the bare |g&lowest;| = 0.44 of GaAs mainly accounts for the observed threshold in the bias voltage between edge states. There is no evidence for the exchange interaction considerably affecting the measured energy gaps at the edge of a two-dimensional electron system. [ABSTRACT FROM AUTHOR]