Cascade of Quantum Phase Transitions in Tunnel-Coupled Edge States

The temperature dependent transport across a quantum Hall line junction was studied. The counterpropagating, tunnel-coupled edge states produced a series of quantum critical points between the highly and weakly tunneling regimes. The conductance near the critical magnetic fields was a function of a single scaling argument according to the scaling analysis. The results show that these critical points indicate a series of quantum phase transitions between two correlated one-dimensional ground states arising due to strong interedge correlation.