Manifestations of phase-coherent transport in graphene
The Josephson effect, weak localization, and aperiodic conductance fluctuations
Kavli Institute of Nanoscience, Delft University of Technology, PO Box 5046, GA 2600, Delft, The Netherlands
Corresponding author: firstname.lastname@example.org
The electronic transport properties of graphene exhibit pronounced differences from those of conventional two dimensional electron systems investigated in the past. As a consequence, well established phenomena such as the integer quantum Hall effect and weak localization manifest themselves differently in graphene. Here we present an overview of recent experiments that we have performed to probe phase coherent transport. In particular, we have investigated in great detail Josephson supercurrent and superconducting proximity effect in junctions consisting of a graphene layer in between superconducting electrodes. We have also used the same devices to measure aperiodic conductance fluctuations and weak localization. The experimental results clearly indicate that low-temperature transport in graphene is phase coherent on a ∼ 1μm length scale, irrespective of the position of the Fermi level. We discuss the different behavior of Josephson supercurrent and weak localization in terms of the unusual properties of the electronic states in graphene upon time reversal symmetry.
© EDP Sciences, Springer-Verlag, 2007