Double point contact in Quantum Hall Line Junctions

TL;DR

This paper demonstrates that multiple point contacts in quantum Hall line junctions cause Aharonov-Bohm oscillations in tunneling conductance, revealing quantum coherence and Luttinger liquid behavior of edge states.

Contribution

It provides a detailed analysis of coherent and incoherent regimes in tunneling conductance for two point contacts, including strong and weak tunneling limits and temperature effects.

Findings

AB oscillations occur in the coherent regime at both strong and weak tunneling.

The oscillation period remains the same across regimes, but the functional form differs.

Temperature influences the coherence and tunneling behavior of the system.

Abstract

We show that multiple point contacts on a barrier separating two laterally coupled quantum Hall fluids induce Aharonov-Bohm (AB) oscillations in the tunneling conductance. These quantum coherence effects provide new evidence for the Luttinger liquid behavior of the edge states of quantum Hall fluids. For a two point contact, we identify coherent and incoherent regimes determined by the relative magnitude of their separation and the temperature. We analyze both regimes in the strong and weak tunneling amplitude limits as well as their temperature dependence. We find that the tunneling conductance should exhibit AB oscillations in the coherent regime, both at strong and weak tunneling amplitude with the same period but with different functional form.