JOSEPHSON EFFECT AND ASSOCIATED PHENOMENA IN DOUBLE-LAYER QUANTUM HALL SYSTEMS

In certain double-layer quantum Hall systems we show the existence of Josephson phenomena such as the Josephson effect, the Meissner effect and the Anderson plasmon excitation. The distinctive feature is that the unit of the charge associated with the Josephson tunneling is e of the single electron and not 2e of the Copper pair. We develop a theory of these Josephson phenomena by using the Chern-Simons formulation of the planar electrons. We explain our results by using the pseudospin language. Furthermore, we point out that Anderson plasmon excitations may already have been observed by a recent experiment on a double-layer quantum Hall system. A microwave experiment without attaching external leads is proposed for a direct observation of plasmon excitations.