Andreev reflection in graphene nanoribbons
arXiv:0806.4475 · doi:10.1103/PhysRevB.79.115131
Abstract
We study Andreev reflection in graphene nanoribbon/superconductor hybrid junctions. By using a tight-binding approach and the scattering formalism we show that finite-size effects lead to notable differences with respect to the bulk graphene case. At subgap voltages, conservation of pseudoparity, a quantum number characterizing the ribbon states, yields either a suppression of Andreev reflection when the ribbon has an even number of sites in the transverse direction or perfect Andreev reflection when the ribbon has an odd number of sites. In the former case the suppression of Andreev reflection induces an insulating behavior even when the junction is biased; electron conduction can however be restored by applying a gate voltage.
6 pages, 6 figures
References in corpus (15)
- The electronic properties of graphene
- Valley filter and valley valve in graphene
- Graphene Nano-Ribbon Electronics
- Andreev reflection and Klein tunneling in graphene
- Bipolar supercurrent in graphene
- Conductance Quantization in Graphene Nanoribbons
- Excitation gap of a graphene channel with superconducting boundaries
- Josephson effect in graphene SBS junctions
- Detecting entangled states in graphene via crossed Andreev reflection
- Pseudo-diffusive magnetotransport in graphene
- Theory of superconductivity of carbon nanotubes and graphene
- Reentrance effect in a graphene n-p-n junction coupled to a superconductor
- Pure spin current in graphene NS structures
- Nonequilibrium valley polarization in graphene nanoconstrictions
- Fine structure of the local pseudogap and Fano effect for superconducting electrons near a zigzag graphene edge